diff --git a/lib/taskana-core/src/main/java/org/taskana/ClassificationService.java b/lib/taskana-core/src/main/java/org/taskana/ClassificationService.java
index d9553eee2..563504892 100644
--- a/lib/taskana-core/src/main/java/org/taskana/ClassificationService.java
+++ b/lib/taskana-core/src/main/java/org/taskana/ClassificationService.java
@@ -3,6 +3,7 @@ package org.taskana;
 import java.util.List;
 
 import org.taskana.model.Classification;
+import org.taskana.persistence.ClassificationQuery;
 
 /**
  * This class manages the classifications.
@@ -43,4 +44,10 @@ public interface ClassificationService {
      *            the Classification to update
      */
     void updateClassification(Classification classification);
+
+    /**
+     * This method provides a query builder for quering the database.
+     * @return a {@link ClassificationQuery}
+     */
+    ClassificationQuery createClassificationQuery();
 }
diff --git a/lib/taskana-core/src/main/java/org/taskana/TaskService.java b/lib/taskana-core/src/main/java/org/taskana/TaskService.java
index c652ca667..0cb2541ac 100644
--- a/lib/taskana-core/src/main/java/org/taskana/TaskService.java
+++ b/lib/taskana-core/src/main/java/org/taskana/TaskService.java
@@ -9,6 +9,7 @@ import org.taskana.model.DueWorkbasketCounter;
 import org.taskana.model.Task;
 import org.taskana.model.TaskState;
 import org.taskana.model.TaskStateCounter;
+import org.taskana.persistence.TaskQuery;
 
 /**
  * The Task Service manages all operations on tasks.
@@ -49,30 +50,6 @@ public interface TaskService {
      */
     Task getTaskById(String taskId) throws TaskNotFoundException;
 
-    /**
-     * Query all tasks for a workbasket.
-     * @param workbasketId
-     *            the workbasket to query
-     * @return the list of tasks, which reside in the workbasket
-     * @throws NotAuthorizedException
-     */
-    List<Task> getTasksForWorkbasket(String workbasketId) throws NotAuthorizedException;
-
-    /**
-     * Query all tasks for a workbasket.
-     * @param workbasketId
-     *            the workbasket to query
-     * @return the list of tasks, which reside in the workbasket
-     * @throws NotAuthorizedException
-     */
-    List<Task> getTasksForWorkbasket(List<String> workbaskets, List<TaskState> states) throws NotAuthorizedException;
-
-    /**
-     * This method returns all Tasks.
-     * @return a {@link List<Task>} of {@link Task}
-     */
-    List<Task> getTasks();
-
     /**
      * This method counts all tasks with a given state.
      * @param states
@@ -81,14 +58,6 @@ public interface TaskService {
      */
     List<TaskStateCounter> getTaskCountForState(List<TaskState> states);
 
-    /**
-     * This method returns all tasks with the specified states.
-     * @param states
-     *            all List with the needed states
-     * @return a list of Tasks
-     */
-    List<Task> findTasks(List<TaskState> states);
-
     /**
      * Count all Tasks in a given workbasket with daysInPast as Days from today in
      * the past and a specific state.
@@ -99,6 +68,8 @@ public interface TaskService {
      */
     long getTaskCountForWorkbasketByDaysInPastAndState(String workbasketId, long daysInPast, List<TaskState> states);
 
+    List<DueWorkbasketCounter> getTaskCountByWorkbasketAndDaysInPastAndState(long daysInPast, List<TaskState> states);
+
     /**
      * Transfer task to another workbasket. The transfer set the transferred flag
      * and resets the read flag.
@@ -119,6 +90,10 @@ public interface TaskService {
      */
     Task setTaskRead(String taskId, boolean isRead) throws TaskNotFoundException;
 
-    List<DueWorkbasketCounter> getTaskCountByWorkbasketAndDaysInPastAndState(long daysInPast, List<TaskState> states);
+    /**
+     * This method provides a query builder for quering the database.
+     * @return a {@link TaskQuery}
+     */
+    TaskQuery createTaskQuery();
 
 }
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/ClassificationServiceImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/ClassificationServiceImpl.java
index c05b56e03..79b496124 100644
--- a/lib/taskana-core/src/main/java/org/taskana/impl/ClassificationServiceImpl.java
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/ClassificationServiceImpl.java
@@ -6,9 +6,12 @@ import java.time.LocalDate;
 import java.util.List;
 
 import org.taskana.ClassificationService;
+import org.taskana.TaskanaEngine;
+import org.taskana.impl.persistence.ClassificationQueryImpl;
 import org.taskana.impl.util.IdGenerator;
 import org.taskana.model.Classification;
 import org.taskana.model.mappings.ClassificationMapper;
+import org.taskana.persistence.ClassificationQuery;
 
 /**
  * This is the implementation of ClassificationService.
@@ -18,9 +21,11 @@ public class ClassificationServiceImpl implements ClassificationService {
     private static final String ID_PREFIX_CLASSIFICATION = "CLI";
 
     private ClassificationMapper classificationMapper;
+    private TaskanaEngine taskanaEngine;
 
-    public ClassificationServiceImpl(ClassificationMapper classificationMapper) {
+    public ClassificationServiceImpl(TaskanaEngine taskanaEngine, ClassificationMapper classificationMapper) {
         super();
+        this.taskanaEngine = taskanaEngine;
         this.classificationMapper = classificationMapper;
     }
 
@@ -76,4 +81,9 @@ public class ClassificationServiceImpl implements ClassificationService {
             }
         }
     }
+
+    @Override
+    public ClassificationQuery createClassificationQuery() {
+        return new ClassificationQueryImpl(taskanaEngine);
+    }
 }
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/TaskServiceImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/TaskServiceImpl.java
index e49a15a41..7c6643d53 100644
--- a/lib/taskana-core/src/main/java/org/taskana/impl/TaskServiceImpl.java
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/TaskServiceImpl.java
@@ -13,6 +13,7 @@ import org.taskana.TaskanaEngine;
 import org.taskana.exceptions.NotAuthorizedException;
 import org.taskana.exceptions.TaskNotFoundException;
 import org.taskana.exceptions.WorkbasketNotFoundException;
+import org.taskana.impl.persistence.TaskQueryImpl;
 import org.taskana.impl.util.IdGenerator;
 import org.taskana.model.DueWorkbasketCounter;
 import org.taskana.model.ObjectReference;
@@ -22,6 +23,8 @@ import org.taskana.model.TaskStateCounter;
 import org.taskana.model.WorkbasketAuthorization;
 import org.taskana.model.mappings.ObjectReferenceMapper;
 import org.taskana.model.mappings.TaskMapper;
+import org.taskana.persistence.TaskQuery;
+
 /**
  * This is the implementation of TaskService.
  */
@@ -113,34 +116,6 @@ public class TaskServiceImpl implements TaskService {
         }
     }
 
-    @Override
-    public List<Task> getTasksForWorkbasket(String workbasketId) throws NotAuthorizedException {
-        taskanaEngine.getWorkbasketService().checkAuthorization(workbasketId, WorkbasketAuthorization.OPEN);
-
-        return taskMapper.findByWorkBasketId(workbasketId);
-    }
-
-    @Override
-    public List<Task> findTasks(List<TaskState> states) {
-        return taskMapper.findByStates(states);
-    }
-
-    @Override
-    public List<Task> getTasksForWorkbasket(List<String> workbasketIds, List<TaskState> states)
-            throws NotAuthorizedException {
-
-        for (String workbasket : workbasketIds) {
-            taskanaEngine.getWorkbasketService().checkAuthorization(workbasket, WorkbasketAuthorization.OPEN);
-        }
-
-        return taskMapper.findByWorkbasketIdsAndStates(workbasketIds, states);
-    }
-
-    @Override
-    public List<Task> getTasks() {
-        return taskMapper.findAll();
-    }
-
     @Override
     public List<TaskStateCounter> getTaskCountForState(List<TaskState> states) {
         return taskMapper.getTaskCountForState(states);
@@ -203,4 +178,8 @@ public class TaskServiceImpl implements TaskService {
         return getTaskById(taskId);
     }
 
+    @Override
+    public TaskQuery createTaskQuery() {
+        return new TaskQueryImpl(taskanaEngine);
+    }
 }
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/TaskanaEngineImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/TaskanaEngineImpl.java
index f357a008a..45a8bf664 100644
--- a/lib/taskana-core/src/main/java/org/taskana/impl/TaskanaEngineImpl.java
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/TaskanaEngineImpl.java
@@ -17,6 +17,7 @@ import org.taskana.impl.persistence.MapTypeHandler;
 import org.taskana.model.mappings.ClassificationMapper;
 import org.taskana.model.mappings.DistributionTargetMapper;
 import org.taskana.model.mappings.ObjectReferenceMapper;
+import org.taskana.model.mappings.QueryMapper;
 import org.taskana.model.mappings.TaskMapper;
 import org.taskana.model.mappings.WorkbasketAccessMapper;
 import org.taskana.model.mappings.WorkbasketMapper;
@@ -71,7 +72,7 @@ public class TaskanaEngineImpl implements TaskanaEngine {
 
     @Override
     public ClassificationService getClassificationService() {
-        return new ClassificationServiceImpl(this.classificationMapper);
+        return new ClassificationServiceImpl(this, this.classificationMapper);
     }
 
     @Override
@@ -104,6 +105,7 @@ public class TaskanaEngineImpl implements TaskanaEngine {
         configuration.addMapper(ClassificationMapper.class);
         configuration.addMapper(WorkbasketAccessMapper.class);
         configuration.addMapper(ObjectReferenceMapper.class);
+        configuration.addMapper(QueryMapper.class);
         configuration.getTypeHandlerRegistry().register(MapTypeHandler.class);
         return new SqlSessionFactoryBuilder().build(configuration);
     }
@@ -116,4 +118,12 @@ public class TaskanaEngineImpl implements TaskanaEngine {
         }
     }
 
+    public SqlSession getSession() {
+        return session;
+    }
+
+    public void setSession(SqlSession session) {
+        this.session = session;
+    }
+
 }
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ClassificationQueryImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ClassificationQueryImpl.java
new file mode 100644
index 000000000..75a844213
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ClassificationQueryImpl.java
@@ -0,0 +1,159 @@
+package org.taskana.impl.persistence;
+
+import java.util.List;
+
+import org.apache.ibatis.session.RowBounds;
+import org.taskana.TaskanaEngine;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.Classification;
+import org.taskana.persistence.ClassificationQuery;
+
+/**
+ * Implementation of ClassificationQuery interface.
+ * @author EH
+ */
+public class ClassificationQueryImpl implements ClassificationQuery {
+
+    private static final String LINK_TO_MAPPER = "org.taskana.model.mappings.QueryMapper.queryClassification";
+    private TaskanaEngineImpl taskanaEngine;
+    private String tenantId;
+    private String[] parentClassificationId;
+    private String[] category;
+    private String[] type;
+    private String[] name;
+    private String description;
+    private int[] priority;
+    private String[] serviceLevel;
+
+    public ClassificationQueryImpl(TaskanaEngine taskanaEngine) {
+        this.taskanaEngine = (TaskanaEngineImpl) taskanaEngine;
+    }
+
+    @Override
+    public ClassificationQuery tenantId(String tenantId) {
+        this.tenantId = tenantId;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery parentClassification(String... parentClassificationId) {
+        this.parentClassificationId = parentClassificationId;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery category(String... category) {
+        this.category = category;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery type(String... type) {
+        this.type = type;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery name(String... name) {
+        this.name = name;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery descriptionLike(String description) {
+        this.description = description;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery priority(int... priorities) {
+        this.priority = priorities;
+        return this;
+    }
+
+    @Override
+    public ClassificationQuery serviceLevel(String... serviceLevel) {
+        this.serviceLevel = serviceLevel;
+        return this;
+    }
+
+    @Override
+    public List<Classification> list() {
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this);
+    }
+
+    @Override
+    public List<Classification> list(int offset, int limit) {
+        RowBounds rowBounds = new RowBounds(offset, limit);
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this, rowBounds);
+    }
+
+    @Override
+    public Classification single() {
+        return taskanaEngine.getSession().selectOne(LINK_TO_MAPPER, this);
+    }
+
+    public String getTenantId() {
+        return tenantId;
+    }
+
+    public void setTenantId(String tenantId) {
+        this.tenantId = tenantId;
+    }
+
+    public String[] getParentClassificationId() {
+        return parentClassificationId;
+    }
+
+    public void setParentClassificationId(String[] parentClassificationId) {
+        this.parentClassificationId = parentClassificationId;
+    }
+
+    public String[] getCategory() {
+        return category;
+    }
+
+    public void setCategory(String[] category) {
+        this.category = category;
+    }
+
+    public String[] getType() {
+        return type;
+    }
+
+    public void setType(String[] type) {
+        this.type = type;
+    }
+
+    public String[] getName() {
+        return name;
+    }
+
+    public void setName(String[] name) {
+        this.name = name;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    public int[] getPriority() {
+        return priority;
+    }
+
+    public void setPriority(int[] priority) {
+        this.priority = priority;
+    }
+
+    public String[] getServiceLevel() {
+        return serviceLevel;
+    }
+
+    public void setServiceLevel(String[] serviceLevel) {
+        this.serviceLevel = serviceLevel;
+    }
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ObjectReferenceQueryImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ObjectReferenceQueryImpl.java
new file mode 100644
index 000000000..8bedc4ef6
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/ObjectReferenceQueryImpl.java
@@ -0,0 +1,130 @@
+package org.taskana.impl.persistence;
+
+import java.util.List;
+
+import org.apache.ibatis.session.RowBounds;
+import org.taskana.TaskanaEngine;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.ObjectReference;
+import org.taskana.persistence.ObjectReferenceQuery;
+
+/**
+ * Implementation of ObjectReferenceQuery interface.
+ * @author EH
+ */
+public class ObjectReferenceQueryImpl implements ObjectReferenceQuery {
+
+    private static final String LINK_TO_MAPPER = "org.taskana.model.mappings.QueryMapper.queryObjectReference";
+
+    private TaskanaEngineImpl taskanaEngine;
+    private String tenantId;
+    private String[] company;
+    private String[] system;
+    private String[] systemInstance;
+    private String[] type;
+    private String[] value;
+
+    public ObjectReferenceQueryImpl(TaskanaEngine taskanaEngine) {
+        this.taskanaEngine = (TaskanaEngineImpl) taskanaEngine;
+    }
+
+    @Override
+    public ObjectReferenceQuery tenantId(String tenantIds) {
+        this.tenantId = tenantIds;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery company(String... companies) {
+        this.company = companies;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery system(String... systems) {
+        this.system = systems;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery systemInstance(String... systemInstances) {
+        this.systemInstance = systemInstances;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery type(String... types) {
+        this.type = types;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery value(String... values) {
+        this.value = values;
+        return this;
+    }
+
+    @Override
+    public List<ObjectReference> list() {
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this);
+    }
+
+    @Override
+    public List<ObjectReference> list(int offset, int limit) {
+        RowBounds rowBounds = new RowBounds(offset, limit);
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this, rowBounds);
+    }
+
+    @Override
+    public ObjectReference single() {
+        return taskanaEngine.getSession().selectOne(LINK_TO_MAPPER, this);
+    }
+
+    public String getTenantId() {
+        return tenantId;
+    }
+
+    public void setTenantId(String tenantId) {
+        this.tenantId = tenantId;
+    }
+
+    public String[] getCompany() {
+        return company;
+    }
+
+    public void setCompany(String[] company) {
+        this.company = company;
+    }
+
+    public String[] getSystem() {
+        return system;
+    }
+
+    public void setSystem(String[] system) {
+        this.system = system;
+    }
+
+    public String[] getSystemInstance() {
+        return systemInstance;
+    }
+
+    public void setSystemInstance(String[] systemInstance) {
+        this.systemInstance = systemInstance;
+    }
+
+    public String[] getType() {
+        return type;
+    }
+
+    public void setType(String[] type) {
+        this.type = type;
+    }
+
+    public String[] getValue() {
+        return value;
+    }
+
+    public void setValue(String[] value) {
+        this.value = value;
+    }
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/impl/persistence/TaskQueryImpl.java b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/TaskQueryImpl.java
new file mode 100644
index 000000000..bf0972e91
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/impl/persistence/TaskQueryImpl.java
@@ -0,0 +1,249 @@
+package org.taskana.impl.persistence;
+
+import java.util.List;
+
+import org.apache.ibatis.session.RowBounds;
+import org.taskana.TaskanaEngine;
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.Task;
+import org.taskana.model.TaskState;
+import org.taskana.model.WorkbasketAuthorization;
+import org.taskana.persistence.ClassificationQuery;
+import org.taskana.persistence.ObjectReferenceQuery;
+import org.taskana.persistence.TaskQuery;
+
+/**
+ * TaskQuery for generating dynamic sql.
+ */
+public class TaskQueryImpl implements TaskQuery {
+
+    private static final String LINK_TO_MAPPER = "org.taskana.model.mappings.QueryMapper.queryTasks";
+
+    private TaskanaEngineImpl taskanaEngine;
+
+    private String tenantId;
+    private String[] name;
+    private String description;
+    private int[] priority;
+    private TaskState[] states;
+    private ClassificationQuery classificationQuery;
+    private String[] workbasketId;
+    private String[] owner;
+    private ObjectReferenceQuery objectReferenceQuery;
+    private Boolean isRead;
+    private Boolean isTransferred;
+    private String[] customFields;
+
+    public TaskQueryImpl(TaskanaEngine taskanaEngine) {
+        this.taskanaEngine = (TaskanaEngineImpl) taskanaEngine;
+    }
+
+    @Override
+    public TaskQuery tenantId(String tenantId) {
+        this.tenantId = tenantId;
+        return this;
+    }
+
+    @Override
+    public TaskQuery name(String... names) {
+        this.name = names;
+        return this;
+    }
+
+    @Override
+    public TaskQuery descriptionLike(String description) {
+        this.description = description;
+        return this;
+    }
+
+    @Override
+    public TaskQuery priority(int... priorities) {
+        this.priority = priorities;
+        return this;
+    }
+
+    @Override
+    public TaskQuery state(TaskState... states) {
+        this.states = states;
+        return this;
+    }
+
+    @Override
+    public TaskQuery classification(ClassificationQuery classificationQuery) {
+        this.classificationQuery = classificationQuery;
+        return this;
+    }
+
+    @Override
+    public TaskQuery workbasketId(String... workbasketIds) {
+        this.workbasketId = workbasketIds;
+        return this;
+    }
+
+    @Override
+    public TaskQuery owner(String... owners) {
+        this.owner = owners;
+        return this;
+    }
+
+    @Override
+    public TaskQuery objectReference(ObjectReferenceQuery objectReferenceQuery) {
+        this.objectReferenceQuery = objectReferenceQuery;
+        return this;
+    }
+
+    @Override
+    public TaskQuery read(Boolean isRead) {
+        this.isRead = isRead;
+        return this;
+    }
+
+    @Override
+    public TaskQuery transferred(Boolean isTransferred) {
+        this.isTransferred = isTransferred;
+        return this;
+    }
+
+    @Override
+    public TaskQuery customFields(String... customFields) {
+        this.customFields = customFields;
+        return this;
+    }
+
+    @Override
+    public ObjectReferenceQuery createObjectReferenceQuery() {
+        return new ObjectReferenceQueryImpl(taskanaEngine);
+    }
+
+    @Override
+    public List<Task> list() throws NotAuthorizedException {
+        checkAuthorization();
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this);
+    }
+
+    @Override
+    public List<Task> list(int offset, int limit) throws NotAuthorizedException {
+        checkAuthorization();
+        RowBounds rowBounds = new RowBounds(offset, limit);
+        return taskanaEngine.getSession().selectList(LINK_TO_MAPPER, this, rowBounds);
+    }
+
+    @Override
+    public Task single() throws NotAuthorizedException {
+        checkAuthorization();
+        return taskanaEngine.getSession().selectOne(LINK_TO_MAPPER, this);
+    }
+
+    private void checkAuthorization() throws NotAuthorizedException {
+        if (this.workbasketId != null && this.workbasketId.length > 0) {
+            for (String workbasket : this.workbasketId) {
+                taskanaEngine.getWorkbasketService().checkAuthorization(workbasket, WorkbasketAuthorization.OPEN);
+            }
+        }
+    }
+
+    public TaskanaEngineImpl getTaskanaEngine() {
+        return taskanaEngine;
+    }
+
+    public void setTaskanaEngine(TaskanaEngineImpl taskanaEngine) {
+        this.taskanaEngine = taskanaEngine;
+    }
+
+    public String getTenantId() {
+        return tenantId;
+    }
+
+    public void setTenantId(String tenantId) {
+        this.tenantId = tenantId;
+    }
+
+    public String[] getName() {
+        return name;
+    }
+
+    public void setName(String[] name) {
+        this.name = name;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    public int[] getPriority() {
+        return priority;
+    }
+
+    public void setPriority(int[] priority) {
+        this.priority = priority;
+    }
+
+    public TaskState[] getStates() {
+        return states;
+    }
+
+    public void setStates(TaskState[] states) {
+        this.states = states;
+    }
+
+    public ClassificationQuery getClassificationQuery() {
+        return classificationQuery;
+    }
+
+    public void setClassificationQuery(ClassificationQuery classificationQuery) {
+        this.classificationQuery = classificationQuery;
+    }
+
+    public String[] getWorkbasketId() {
+        return workbasketId;
+    }
+
+    public void setWorkbasketId(String[] workbasketId) {
+        this.workbasketId = workbasketId;
+    }
+
+    public String[] getOwner() {
+        return owner;
+    }
+
+    public void setOwner(String[] owner) {
+        this.owner = owner;
+    }
+
+    public ObjectReferenceQuery getObjectReferenceQuery() {
+        return objectReferenceQuery;
+    }
+
+    public void setObjectReferenceQuery(ObjectReferenceQuery objectReferenceQuery) {
+        this.objectReferenceQuery = objectReferenceQuery;
+    }
+
+    public boolean isRead() {
+        return isRead;
+    }
+
+    public void setRead(boolean isRead) {
+        this.isRead = isRead;
+    }
+
+    public boolean isTransferred() {
+        return isTransferred;
+    }
+
+    public void setTransferred(boolean isTransferred) {
+        this.isTransferred = isTransferred;
+    }
+
+    public String[] getCustomFields() {
+        return customFields;
+    }
+
+    public void setCustomFields(String[] customFields) {
+        this.customFields = customFields;
+    }
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/model/mappings/QueryMapper.java b/lib/taskana-core/src/main/java/org/taskana/model/mappings/QueryMapper.java
new file mode 100644
index 000000000..c09f8af7e
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/model/mappings/QueryMapper.java
@@ -0,0 +1,139 @@
+package org.taskana.model.mappings;
+
+import java.util.List;
+
+import org.apache.ibatis.annotations.One;
+import org.apache.ibatis.annotations.Result;
+import org.apache.ibatis.annotations.Results;
+import org.apache.ibatis.annotations.Select;
+import org.taskana.impl.persistence.ClassificationQueryImpl;
+import org.taskana.impl.persistence.ObjectReferenceQueryImpl;
+import org.taskana.impl.persistence.TaskQueryImpl;
+import org.taskana.model.Classification;
+import org.taskana.model.ObjectReference;
+import org.taskana.model.Task;
+
+/**
+ * This class provides a mapper for all queries.
+ */
+public interface QueryMapper {
+
+    String OBJECTREFERENCEMAPPER_FINDBYID = "org.taskana.model.mappings.ObjectReferenceMapper.findById";
+    String CLASSIFICATION_FINDBYID = "org.taskana.model.mappings.ClassificationMapper.findById";
+
+    @Select("<script>SELECT t.ID, t.TENANT_ID, t.CREATED, t.CLAIMED, t.COMPLETED, t.MODIFIED, t.PLANNED, t.DUE, t.NAME, t.DESCRIPTION, t.PRIORITY, t.STATE, t.CLASSIFICATION_ID, t.WORKBASKETID, t.OWNER, t.PRIMARY_OBJ_REF_ID, t.IS_READ, t.IS_TRANSFERRED, t.CUSTOM_1, t.CUSTOM_2, t.CUSTOM_3, t.CUSTOM_4, t.CUSTOM_5, t.CUSTOM_6, t.CUSTOM_7, t.CUSTOM_8, t.CUSTOM_9, t.CUSTOM_10 "
+            + "FROM TASK t "
+            // Joins if Classification or Object Reference Query is needed
+            + "<if test='classificationQuery != null'>LEFT OUTER JOIN CLASSIFICATION c on t.CLASSIFICATION_ID = c.ID</if> "
+            + "<if test='objectReferenceQuery != null'>LEFT OUTER JOIN OBJECT_REFERENCE o on t.PRIMARY_OBJ_REF_ID = o.ID</if> "
+            + "<where>"
+            + "<if test='tenantId != null'>t.TENANT_ID = #{tenantId}</if> "
+            + "<if test='name != null'>AND t.NAME IN(<foreach item='item' collection='name' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='description != null'>AND t.DESCRIPTION like #{description}</if> "
+            + "<if test='priority != null'>AND t.PRIORITY IN(<foreach item='item' collection='priority' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='states != null'>AND t.STATE IN(<foreach item='item' collection='states' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='workbasketId != null'>AND t.WORKBASKETID IN(<foreach item='item' collection='workbasketId' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='owner != null'>AND t.OWNER IN(<foreach item='item' collection='owner' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='isRead != null'>AND t.IS_READ = #{isRead}</if> "
+            + "<if test='isTransferred != null'>AND t.IS_TRANSFERRED = #{isTransferred}</if> "
+            + "<if test='customFields != null'>AND (t.CUSTOM_1 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_2 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_3 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_4 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_5 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_6 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_7 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_8 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_9 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>) OR t.CUSTOM_10 IN(<foreach item='item' collection='customFields' separator=',' >#{item}</foreach>))</if> "
+            // Classification Query
+            + "<if test='classificationQuery != null'>"
+            + "<if test='classificationQuery.tenantId != null'>AND c.TENANT_ID = #{classificationQuery.tenantId}</if> "
+            + "<if test='classificationQuery.parentClassificationId != null'>AND c.PARENT_CLASSIFICATION_ID IN(<foreach item='item' collection='classificationQuery.parentClassificationId' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='classificationQuery.category != null'>AND c.CATEGORY IN(<foreach item='item' collection='classificationQuery.category' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='classificationQuery.type != null'>AND c.TYPE IN(<foreach item='item' collection='classificationQuery.type' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='classificationQuery.name != null'>AND c.NAME IN(<foreach item='item' collection='classificationQuery.name' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='classificationQuery.description != null'>AND c.DESCRIPTION like #{classificationQuery.description}</if> "
+            + "<if test='classificationQuery.priority != null'>AND c.PRIORITY IN(<foreach item='item' collection='classificationQuery.priority' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='classificationQuery.serviceLevel != null'>AND c.SERVICE_LEVEL IN(<foreach item='item' collection='classificationQuery.serviceLevel' separator=',' >#{item}</foreach>)</if> "
+            + "</if>"
+            // Object Reference Query
+            + "<if test='objectReferenceQuery != null'>"
+            + "<if test='objectReferenceQuery.tenantId != null'>AND o.TENANT_ID = #{objectReferenceQuery.tenantId}</if> "
+            + "<if test='objectReferenceQuery.company != null'>AND o.COMPANY IN(<foreach item='item' collection='objectReferenceQuery.company' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='objectReferenceQuery.system != null'>AND o.SYSTEM IN(<foreach item='item' collection='objectReferenceQuery.system' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='objectReferenceQuery.systemInstance != null'>AND o.SYSTEM_INSTANCE IN(<foreach item='item' collection='objectReferenceQuery.systemInstance' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='objectReferenceQuery.type != null'>AND o.TYPE IN(<foreach item='item' collection='objectReferenceQuery.type' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='objectReferenceQuery.value != null'>AND o.VALUE IN(<foreach item='item' collection='objectReferenceQuery.value' separator=',' >#{item}</foreach>)</if> "
+            + "</if>"
+            + "</where>"
+            + "</script>")
+    @Results(value = { @Result(property = "id", column = "ID"),
+            @Result(property = "tenantId", column = "TENANT_ID"),
+            @Result(property = "created", column = "CREATED"),
+            @Result(property = "claimed", column = "CLAIMED"),
+            @Result(property = "completed", column = "COMPLETED"),
+            @Result(property = "modified", column = "MODIFIED"),
+            @Result(property = "planned", column = "PLANNED"),
+            @Result(property = "due", column = "DUE"),
+            @Result(property = "name", column = "NAME"),
+            @Result(property = "description", column = "DESCRIPTION"),
+            @Result(property = "priority", column = "PRIORITY"),
+            @Result(property = "state", column = "STATE"),
+            @Result(property = "classification", column = "CLASSIFICATION_ID", javaType = Classification.class, one = @One(select = CLASSIFICATION_FINDBYID)),
+            @Result(property = "workbasketId", column = "WORKBASKETID"),
+            @Result(property = "owner", column = "OWNER"),
+            @Result(property = "primaryObjRef", column = "PRIMARY_OBJ_REF_ID", javaType = ObjectReference.class, one = @One(select = OBJECTREFERENCEMAPPER_FINDBYID)),
+            @Result(property = "isRead", column = "IS_READ"),
+            @Result(property = "isTransferred", column = "IS_TRANSFERRED"),
+            @Result(property = "custom1", column = "CUSTOM_1"),
+            @Result(property = "custom2", column = "CUSTOM_2"),
+            @Result(property = "custom3", column = "CUSTOM_3"),
+            @Result(property = "custom4", column = "CUSTOM_4"),
+            @Result(property = "custom5", column = "CUSTOM_5"),
+            @Result(property = "custom6", column = "CUSTOM_6"),
+            @Result(property = "custom7", column = "CUSTOM_7"),
+            @Result(property = "custom8", column = "CUSTOM_8"),
+            @Result(property = "custom9", column = "CUSTOM_9"),
+            @Result(property = "custom10", column = "CUSTOM_10") })
+    List<Task> queryTasks(TaskQueryImpl taskQuery);
+
+    @Select("<script>SELECT ID, TENANT_ID, PARENT_CLASSIFICATION_ID, CATEGORY, TYPE, CREATED, MODIFIED, NAME, DESCRIPTION, PRIORITY, SERVICE_LEVEL "
+            + "FROM CLASSIFICATION "
+            + "<where>"
+            + "<if test='tenantId != null'>TENANT_ID = #{tenantId}</if> "
+            + "<if test='parentClassificationId != null'>AND PARENT_CLASSIFICATION_ID IN(<foreach item='item' collection='parentClassificationId' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='category != null'>AND CATEGORY IN(<foreach item='item' collection='category' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='type != null'>AND TYPE IN(<foreach item='item' collection='type' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='name != null'>AND NAME IN(<foreach item='item' collection='name' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='description != null'>AND DESCRIPTION like #{description}</if> "
+            + "<if test='priority != null'>AND PRIORITY IN(<foreach item='item' collection='.priority' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='serviceLevel != null'>AND SERVICE_LEVEL IN(<foreach item='item' collection='serviceLevel' separator=',' >#{item}</foreach>)</if> "
+            + "</where>"
+            + "</script>")
+    @Results({ @Result(property = "id", column = "ID"),
+            @Result(property = "tenantId", column = "TENANT_ID"),
+            @Result(property = "parentClassificationId", column = "PARENT_CLASSIFICATION_ID"),
+            @Result(property = "category", column = "CATEGORY"),
+            @Result(property = "type", column = "TYPE"),
+            @Result(property = "created", column = "CREATED"),
+            @Result(property = "modified", column = "MODIFIED"),
+            @Result(property = "name", column = "NAME"),
+            @Result(property = "description", column = "DESCRIPTION"),
+            @Result(property = "priority", column = "PRIORITY"),
+            @Result(property = "serviceLevel", column = "SERVICE_LEVEL") })
+    List<Classification> queryClassification(ClassificationQueryImpl classificationQuery);
+
+
+    @Select("<script>SELECT ID, TENANT_ID, COMPANY, SYSTEM, SYSTEM_INSTANCE, TYPE, VALUE "
+            + "FROM OBJECT_REFERENCE "
+            + "<where>"
+            + "<if test='tenantId != null'>TENANT_ID = #{tenantId}</if> "
+            + "<if test='company != null'>AND COMPANY IN(<foreach item='item' collection='company' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='system != null'>AND SYSTEM IN(<foreach item='item' collection='system' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='systemInstance != null'>AND SYSTEM_INSTANCE IN(<foreach item='item' collection='systemInstance' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='type != null'>AND TYPE IN(<foreach item='item' collection='type' separator=',' >#{item}</foreach>)</if> "
+            + "<if test='value != null'>AND VALUE IN(<foreach item='item' collection='value' separator=',' >#{item}</foreach>)</if> "
+            + "</where>"
+            + "</script>")
+    @Results({
+        @Result(property = "id", column = "ID"),
+        @Result(property = "tenantId", column = "TENANT_ID"),
+        @Result(property = "company", column = "COMPANY"),
+        @Result(property = "system", column = "SYSTEM"),
+        @Result(property = "systemInstance", column = "SYSTEM_INSTANCE"),
+        @Result(property = "type", column = "TYPE"),
+        @Result(property = "value", column = "VALUE") })
+    List<ObjectReference> queryObjectReference(ObjectReferenceQueryImpl objectReference);
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/model/mappings/TaskMapper.java b/lib/taskana-core/src/main/java/org/taskana/model/mappings/TaskMapper.java
index b3fac1b9b..0e781f4d9 100644
--- a/lib/taskana-core/src/main/java/org/taskana/model/mappings/TaskMapper.java
+++ b/lib/taskana-core/src/main/java/org/taskana/model/mappings/TaskMapper.java
@@ -66,153 +66,6 @@ public interface TaskMapper {
     })
     Task findById(@Param("id") String id);
 
-    @Select("SELECT ID, TENANT_ID, CREATED, CLAIMED, COMPLETED, MODIFIED, PLANNED, DUE, NAME, DESCRIPTION, PRIORITY, STATE, CLASSIFICATION_ID, WORKBASKETID, OWNER, PRIMARY_OBJ_REF_ID, IS_READ, IS_TRANSFERRED, CUSTOM_1, CUSTOM_2, CUSTOM_3, CUSTOM_4, CUSTOM_5, CUSTOM_6, CUSTOM_7, CUSTOM_8, CUSTOM_9, CUSTOM_10 "
-            + "FROM TASK "
-            + "WHERE WORKBASKETID = #{workbasketId} "
-            + "ORDER BY ID")
-    @Results(value = {
-            @Result(property = "id", column = "ID"),
-            @Result(property = "tenantId", column = "TENANT_ID"),
-            @Result(property = "created", column = "CREATED"),
-            @Result(property = "claimed", column = "CLAIMED"),
-            @Result(property = "completed", column = "COMPLETED"),
-            @Result(property = "modified", column = "MODIFIED"),
-            @Result(property = "planned", column = "PLANNED"),
-            @Result(property = "due", column = "DUE"),
-            @Result(property = "name", column = "NAME"),
-            @Result(property = "description", column = "DESCRIPTION"),
-            @Result(property = "priority", column = "PRIORITY"),
-            @Result(property = "state", column = "STATE"),
-            @Result(property = "classification", column = "CLASSIFICATION_ID", javaType = Classification.class, one = @One(select = CLASSIFICATION_FINDBYID)),
-            @Result(property = "workbasketId", column = "WORKBASKETID"),
-            @Result(property = "owner", column = "OWNER"),
-            @Result(property = "primaryObjRef", column = "PRIMARY_OBJ_REF_ID", javaType = ObjectReference.class, one = @One(select = OBJECTREFERENCEMAPPER_FINDBYID)),
-            @Result(property = "isRead", column = "IS_READ"),
-            @Result(property = "isTransferred", column = "IS_TRANSFERRED"),
-            @Result(property = "custom1", column = "CUSTOM_1"),
-            @Result(property = "custom2", column = "CUSTOM_2"),
-            @Result(property = "custom3", column = "CUSTOM_3"),
-            @Result(property = "custom4", column = "CUSTOM_4"),
-            @Result(property = "custom5", column = "CUSTOM_5"),
-            @Result(property = "custom6", column = "CUSTOM_6"),
-            @Result(property = "custom7", column = "CUSTOM_7"),
-            @Result(property = "custom8", column = "CUSTOM_8"),
-            @Result(property = "custom9", column = "CUSTOM_9"),
-            @Result(property = "custom10", column = "CUSTOM_10")
-    })
-    List<Task> findByWorkBasketId(@Param("workbasketId") String workbasketId);
-
-    @Select("<script>"
-            + "SELECT ID, TENANT_ID, CREATED, CLAIMED, COMPLETED, MODIFIED, PLANNED, DUE, NAME, DESCRIPTION, PRIORITY, STATE, CLASSIFICATION_ID, WORKBASKETID, OWNER, PRIMARY_OBJ_REF_ID, IS_READ, IS_TRANSFERRED, CUSTOM_1, CUSTOM_2, CUSTOM_3, CUSTOM_4, CUSTOM_5, CUSTOM_6, CUSTOM_7, CUSTOM_8, CUSTOM_9, CUSTOM_10  "
-            + "FROM TASK "
-            + "WHERE WORKBASKETID IN (<foreach item='item' collection='workbasketIds' separator=','>#{item}</foreach>) "
-            + "AND STATE IN (<foreach item='item' collection='states' separator=',' >#{item}</foreach>) "
-            + "ORDER BY ID"
-            + "</script>")
-    @Results(value = {
-            @Result(property = "id", column = "ID"),
-            @Result(property = "tenantId", column = "TENANT_ID"),
-            @Result(property = "created", column = "CREATED"),
-            @Result(property = "claimed", column = "CLAIMED"),
-            @Result(property = "completed", column = "COMPLETED"),
-            @Result(property = "modified", column = "MODIFIED"),
-            @Result(property = "planned", column = "PLANNED"),
-            @Result(property = "due", column = "DUE"),
-            @Result(property = "name", column = "NAME"),
-            @Result(property = "description", column = "DESCRIPTION"),
-            @Result(property = "priority", column = "PRIORITY"),
-            @Result(property = "state", column = "STATE"),
-            @Result(property = "classification", column = "CLASSIFICATION_ID", javaType = Classification.class, one = @One(select = CLASSIFICATION_FINDBYID)),
-            @Result(property = "workbasketId", column = "WORKBASKETID"),
-            @Result(property = "owner", column = "OWNER"),
-            @Result(property = "primaryObjRef", column = "PRIMARY_OBJ_REF_ID", javaType = ObjectReference.class, one = @One(select = OBJECTREFERENCEMAPPER_FINDBYID)),
-            @Result(property = "isRead", column = "IS_READ"),
-            @Result(property = "isTransferred", column = "IS_TRANSFERRED"),
-            @Result(property = "custom1", column = "CUSTOM_1"),
-            @Result(property = "custom2", column = "CUSTOM_2"),
-            @Result(property = "custom3", column = "CUSTOM_3"),
-            @Result(property = "custom4", column = "CUSTOM_4"),
-            @Result(property = "custom5", column = "CUSTOM_5"),
-            @Result(property = "custom6", column = "CUSTOM_6"),
-            @Result(property = "custom7", column = "CUSTOM_7"),
-            @Result(property = "custom8", column = "CUSTOM_8"),
-            @Result(property = "custom9", column = "CUSTOM_9"),
-            @Result(property = "custom10", column = "CUSTOM_10")
-    })
-    List<Task> findByWorkbasketIdsAndStates(@Param("workbasketIds") List<String> workbasketIds, @Param("states") List<TaskState> states);
-
-    @Select("<script>"
-            + "SELECT ID, TENANT_ID, CREATED, CLAIMED, COMPLETED, MODIFIED, PLANNED, DUE, NAME, DESCRIPTION, PRIORITY, STATE, CLASSIFICATION_ID, WORKBASKETID, OWNER, PRIMARY_OBJ_REF_ID, IS_READ, IS_TRANSFERRED, CUSTOM_1, CUSTOM_2, CUSTOM_3, CUSTOM_4, CUSTOM_5, CUSTOM_6, CUSTOM_7, CUSTOM_8, CUSTOM_9, CUSTOM_10 "
-            + "FROM TASK "
-            + "WHERE STATE IN (<foreach item='item' collection='states' separator=',' >#{item}</foreach>) "
-            + "ORDER BY ID"
-            + "</script>")
-    @Results(value = {
-            @Result(property = "id", column = "ID"),
-            @Result(property = "tenantId", column = "TENANT_ID"),
-            @Result(property = "created", column = "CREATED"),
-            @Result(property = "claimed", column = "CLAIMED"),
-            @Result(property = "completed", column = "COMPLETED"),
-            @Result(property = "modified", column = "MODIFIED"),
-            @Result(property = "planned", column = "PLANNED"),
-            @Result(property = "due", column = "DUE"),
-            @Result(property = "name", column = "NAME"),
-            @Result(property = "description", column = "DESCRIPTION"),
-            @Result(property = "priority", column = "PRIORITY"),
-            @Result(property = "state", column = "STATE"),
-            @Result(property = "classification", column = "CLASSIFICATION_ID", javaType = Classification.class, one = @One(select = CLASSIFICATION_FINDBYID)),
-            @Result(property = "workbasketId", column = "WORKBASKETID"),
-            @Result(property = "owner", column = "OWNER"),
-            @Result(property = "primaryObjRef", column = "PRIMARY_OBJ_REF_ID", javaType = ObjectReference.class, one = @One(select = OBJECTREFERENCEMAPPER_FINDBYID)),
-            @Result(property = "isRead", column = "IS_READ"),
-            @Result(property = "isTransferred", column = "IS_TRANSFERRED"),
-            @Result(property = "custom1", column = "CUSTOM_1"),
-            @Result(property = "custom2", column = "CUSTOM_2"),
-            @Result(property = "custom3", column = "CUSTOM_3"),
-            @Result(property = "custom4", column = "CUSTOM_4"),
-            @Result(property = "custom5", column = "CUSTOM_5"),
-            @Result(property = "custom6", column = "CUSTOM_6"),
-            @Result(property = "custom7", column = "CUSTOM_7"),
-            @Result(property = "custom8", column = "CUSTOM_8"),
-            @Result(property = "custom9", column = "CUSTOM_9"),
-            @Result(property = "custom10", column = "CUSTOM_10")
-    })
-    List<Task> findByStates(@Param("states") List<TaskState> states);
-
-    @Select("SELECT ID, TENANT_ID, CREATED, CLAIMED, COMPLETED, MODIFIED, PLANNED, DUE, NAME, DESCRIPTION, PRIORITY, STATE, CLASSIFICATION_ID, WORKBASKETID, OWNER, PRIMARY_OBJ_REF_ID, IS_READ, IS_TRANSFERRED, CUSTOM_1, CUSTOM_2, CUSTOM_3, CUSTOM_4, CUSTOM_5, CUSTOM_6, CUSTOM_7, CUSTOM_8, CUSTOM_9, CUSTOM_10 "
-            + "FROM TASK ")
-    @Results(value = {
-            @Result(property = "id", column = "ID"),
-            @Result(property = "tenantId", column = "TENANT_ID"),
-            @Result(property = "created", column = "CREATED"),
-            @Result(property = "claimed", column = "CLAIMED"),
-            @Result(property = "completed", column = "COMPLETED"),
-            @Result(property = "modified", column = "MODIFIED"),
-            @Result(property = "planned", column = "PLANNED"),
-            @Result(property = "due", column = "DUE"),
-            @Result(property = "name", column = "NAME"),
-            @Result(property = "description", column = "DESCRIPTION"),
-            @Result(property = "priority", column = "PRIORITY"),
-            @Result(property = "state", column = "STATE"),
-            @Result(property = "classification", column = "CLASSIFICATION_ID", javaType = Classification.class, one = @One(select = CLASSIFICATION_FINDBYID)),
-            @Result(property = "workbasketId", column = "WORKBASKETID"),
-            @Result(property = "owner", column = "OWNER"),
-            @Result(property = "primaryObjRef", column = "PRIMARY_OBJ_REF_ID", javaType = ObjectReference.class, one = @One(select = OBJECTREFERENCEMAPPER_FINDBYID)),
-            @Result(property = "isRead", column = "IS_READ"),
-            @Result(property = "isTransferred", column = "IS_TRANSFERRED"),
-            @Result(property = "custom1", column = "CUSTOM_1"),
-            @Result(property = "custom2", column = "CUSTOM_2"),
-            @Result(property = "custom3", column = "CUSTOM_3"),
-            @Result(property = "custom4", column = "CUSTOM_4"),
-            @Result(property = "custom5", column = "CUSTOM_5"),
-            @Result(property = "custom6", column = "CUSTOM_6"),
-            @Result(property = "custom7", column = "CUSTOM_7"),
-            @Result(property = "custom8", column = "CUSTOM_8"),
-            @Result(property = "custom9", column = "CUSTOM_9"),
-            @Result(property = "custom10", column = "CUSTOM_10")
-    })
-    List<Task> findAll();
-
     @Select("<script>"
             + "SELECT STATE, COUNT (STATE) as counter "
             + "FROM TASK "
diff --git a/lib/taskana-core/src/main/java/org/taskana/persistence/BaseQuery.java b/lib/taskana-core/src/main/java/org/taskana/persistence/BaseQuery.java
new file mode 100644
index 000000000..1a121b1e5
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/persistence/BaseQuery.java
@@ -0,0 +1,39 @@
+package org.taskana.persistence;
+
+import java.util.List;
+
+import org.taskana.exceptions.NotAuthorizedException;
+
+/**
+ * Main query interface.
+ * @author EH
+ * @param <T>
+ *            specifies the return type of the follwing methods
+ */
+public interface BaseQuery<T> {
+
+    /**
+     * This method will return a list of defined {@link T} objects.
+     * @return
+     * @throws NotAuthorizedException
+     */
+    List<T> list() throws NotAuthorizedException;
+
+    /**
+     * This method will return a list of defined {@link T} objects with specified
+     * offset and an limit.
+     * @param offset
+     * @param limit
+     * @return
+     * @throws NotAuthorizedException
+     */
+    List<T> list(int offset, int limit) throws NotAuthorizedException;
+
+    /**
+     * This method will return a single object of {@link T}.
+     * @return
+     * @throws NotAuthorizedException
+     */
+    T single() throws NotAuthorizedException;
+
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/persistence/ClassificationQuery.java b/lib/taskana-core/src/main/java/org/taskana/persistence/ClassificationQuery.java
new file mode 100644
index 000000000..9aef01553
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/persistence/ClassificationQuery.java
@@ -0,0 +1,74 @@
+package org.taskana.persistence;
+
+import org.taskana.model.Classification;
+
+/**
+ * ClassificationQuery for generating dynamic sql.
+ */
+public interface ClassificationQuery extends BaseQuery<Classification> {
+    /**
+     * Add your tenant id to your query.
+     * @param tenantId
+     *            the tenant id as String
+     * @return the query
+     */
+    ClassificationQuery tenantId(String tenantId);
+
+    /**
+     * Add your parentClassification to your query.
+     * @param parentClassificationId
+     *            as String
+     * @return the query
+     */
+    ClassificationQuery parentClassification(String... parentClassificationId);
+
+    /**
+     * Add your category to your query.
+     * @param category
+     *            as String
+     * @return the query
+     */
+    ClassificationQuery category(String... category);
+
+    /**
+     * Add your type to your query.
+     * @param type
+     *            as String
+     * @return the query
+     */
+    ClassificationQuery type(String... type);
+
+    /**
+     * Add your name to your query.
+     * @param name
+     *            as String
+     * @return the query
+     */
+    ClassificationQuery name(String... name);
+
+    /**
+     * Add your description to your query. It will be compared in SQL with an LIKE.
+     * If you use a wildcard like % tehn it will be transmitted to the database.
+     * @param description
+     *            your description
+     * @return the query
+     */
+    ClassificationQuery descriptionLike(String description);
+
+    /**
+     * Add your priority to your query.
+     * @param priorities
+     *            as integers
+     * @return the query
+     */
+    ClassificationQuery priority(int... priorities);
+
+    /**
+     * Add your serviceLevel to your query.
+     * @param serviceLevel
+     *            as String
+     * @return the query
+     */
+    ClassificationQuery serviceLevel(String... serviceLevel);
+
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/persistence/ObjectReferenceQuery.java b/lib/taskana-core/src/main/java/org/taskana/persistence/ObjectReferenceQuery.java
new file mode 100644
index 000000000..e22c94e98
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/persistence/ObjectReferenceQuery.java
@@ -0,0 +1,57 @@
+package org.taskana.persistence;
+
+import org.taskana.model.ObjectReference;
+
+/**
+ * ObjectReferenceQuery for generating dynamic sql.
+ */
+public interface ObjectReferenceQuery extends BaseQuery<ObjectReference> {
+    /**
+     * Add your tenant id to your query.
+     * @param tenantId
+     *            the tenant id as String
+     * @return the query
+     */
+    ObjectReferenceQuery tenantId(String tenantId);
+
+    /**
+     * Add your company to your query.
+     * @param companies
+     *            as Strings
+     * @return the query
+     */
+    ObjectReferenceQuery company(String... companies);
+
+    /**
+     * Add your system to your query.
+     * @param systems
+     *            as Strings
+     * @return the query
+     */
+    ObjectReferenceQuery system(String... systems);
+
+    /**
+     * Add your systemInstance to your query.
+     * @param systemInstances
+     *            as Strings
+     * @return the query
+     */
+    ObjectReferenceQuery systemInstance(String... systemInstances);
+
+    /**
+     * Add your type to your query.
+     * @param types
+     *            as Strings
+     * @return the query
+     */
+    ObjectReferenceQuery type(String... types);
+
+    /**
+     * Add your value to your query.
+     * @param values
+     *            as Strings
+     * @return the query
+     */
+    ObjectReferenceQuery value(String... values);
+
+}
diff --git a/lib/taskana-core/src/main/java/org/taskana/persistence/TaskQuery.java b/lib/taskana-core/src/main/java/org/taskana/persistence/TaskQuery.java
new file mode 100644
index 000000000..a2a0ce551
--- /dev/null
+++ b/lib/taskana-core/src/main/java/org/taskana/persistence/TaskQuery.java
@@ -0,0 +1,122 @@
+package org.taskana.persistence;
+
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.model.Task;
+import org.taskana.model.TaskState;
+
+/**
+ * TaskQuery for generating dynamic sql.
+ */
+public interface TaskQuery extends BaseQuery<Task> {
+
+    /**
+     * Add your tenant id to your query.
+     * @param tenantId
+     *            the tenant id as String
+     * @return the query
+     */
+    TaskQuery tenantId(String tenantId);
+
+    /**
+     * Add your names to your query.
+     * @param name
+     *            the names as Strings
+     * @return the query
+     */
+    TaskQuery name(String... name);
+
+    /**
+     * Add your description to your query. It will be compared in SQL with an LIKE.
+     * If you use a wildcard like % tehn it will be transmitted to the database.
+     * @param description
+     *            your description
+     * @return the query
+     */
+    TaskQuery descriptionLike(String description);
+
+    /**
+     * Add your priorities to your query.
+     * @param priorities
+     *            as a integer
+     * @return the query
+     */
+    TaskQuery priority(int... priorities);
+
+    /**
+     * Add your state to your query.
+     * @param states
+     *            the states as {@link TaskState}
+     * @return the query
+     */
+    TaskQuery state(TaskState... states);
+
+    /**
+     * Add your classification to your query. The classification query can be
+     * obtained from the ClassificationService
+     * @param classificationQuery
+     *            the classification query
+     * @return the query
+     */
+    TaskQuery classification(ClassificationQuery classificationQuery);
+
+    /**
+     * Add your workbasket id to the query.
+     * @param workbasketIds
+     *            the workbasket ids as String
+     * @return the query
+     * @throws NotAuthorizedException
+     *             if the user have no rights
+     */
+    TaskQuery workbasketId(String... workbasketIds) throws NotAuthorizedException;
+
+    /**
+     * Add the owners to your query.
+     * @param owners
+     *            the owners as String
+     * @return the query
+     */
+    TaskQuery owner(String... owners);
+
+    /**
+     * Add your objectReference to your query. The objectReference query can be
+     * obtained from the TaskService
+     * @param objectReferenceQuery
+     *            the objectReference query
+     * @return the query
+     */
+    TaskQuery objectReference(ObjectReferenceQuery objectReferenceQuery);
+
+    /**
+     * Add the isRead flag to the query.
+     * @param isRead
+     *            as Boolean. If null, it won't be integrated into the statement.
+     *            You have to set false.
+     * @return the query
+     */
+    TaskQuery read(Boolean isRead);
+
+    /**
+     * Add the isTransferred flag to the query.
+     * @param isTransferred
+     *            as Boolean. If null, it won't be integrated into the statement.
+     *            You have to set false.
+     * @return the query
+     */
+    TaskQuery transferred(Boolean isTransferred);
+
+    /**
+     * Filter the custom fields with this query. The scan will be run over all 10
+     * fields.
+     * @param customFields
+     *            the value in the fields
+     * @return the query
+     */
+    TaskQuery customFields(String... customFields);
+
+    /**
+     * This method provides a query builder for quering the database.
+     * @return a {@link ObjectReferenceQuery}
+     */
+    ObjectReferenceQuery createObjectReferenceQuery();
+
+}
diff --git a/lib/taskana-core/src/test/java/org/taskana/impl/TaskServiceImplTest.java b/lib/taskana-core/src/test/java/org/taskana/impl/TaskServiceImplTest.java
index 23ee0f42e..72328a3bc 100644
--- a/lib/taskana-core/src/test/java/org/taskana/impl/TaskServiceImplTest.java
+++ b/lib/taskana-core/src/test/java/org/taskana/impl/TaskServiceImplTest.java
@@ -4,8 +4,6 @@ import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 
 import java.sql.Timestamp;
-import java.util.ArrayList;
-import java.util.List;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -33,7 +31,6 @@ import org.taskana.model.mappings.TaskMapper;
 @RunWith(MockitoJUnitRunner.class)
 public class TaskServiceImplTest {
 
-    private static final int LIST_SIZE = 3;
     private static final int SLEEP_TIME = 100;
     @InjectMocks
     TaskServiceImpl taskServiceImpl;
@@ -101,19 +98,6 @@ public class TaskServiceImplTest {
         taskServiceImpl.complete("test");
     }
 
-    @Test
-    public void testGetTasksForWorkbasket() throws NotAuthorizedException {
-        registerBasicMocks(false);
-        ArrayList<Task> tasks = new ArrayList<Task>();
-        tasks.add(createUnitTestTask("1", "Unit Test Task 1", "1"));
-        tasks.add(createUnitTestTask("2", "Unit Test Task 2", "1"));
-        tasks.add(createUnitTestTask("3", "Unit Test Task 3", "1"));
-        Mockito.when(taskMapper.findByWorkBasketId("1")).thenReturn(tasks);
-
-        List<Task> list = taskServiceImpl.getTasksForWorkbasket("1");
-        Assert.assertEquals(LIST_SIZE, list.size());
-    }
-
     @Test
     public void testTransferTaskZuDestinationWorkbasket()
             throws TaskNotFoundException, WorkbasketNotFoundException, NotAuthorizedException {
diff --git a/lib/taskana-core/src/test/java/org/taskana/impl/integration/TaskServiceImplTransactionTest.java b/lib/taskana-core/src/test/java/org/taskana/impl/integration/TaskServiceImplTransactionTest.java
index 6311b6122..54708e4be 100644
--- a/lib/taskana-core/src/test/java/org/taskana/impl/integration/TaskServiceImplTransactionTest.java
+++ b/lib/taskana-core/src/test/java/org/taskana/impl/integration/TaskServiceImplTransactionTest.java
@@ -1,5 +1,9 @@
 package org.taskana.impl.integration;
 
+import java.io.FileNotFoundException;
+import java.sql.SQLException;
+import java.util.List;
+
 import org.h2.jdbcx.JdbcDataSource;
 import org.junit.Assert;
 import org.junit.Test;
@@ -9,10 +13,12 @@ import org.taskana.exceptions.NotAuthorizedException;
 import org.taskana.exceptions.TaskNotFoundException;
 import org.taskana.impl.TaskServiceImpl;
 import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.impl.persistence.ClassificationQueryImpl;
+import org.taskana.impl.persistence.ObjectReferenceQueryImpl;
 import org.taskana.model.Task;
-
-import java.io.FileNotFoundException;
-import java.sql.SQLException;
+import org.taskana.model.TaskState;
+import org.taskana.persistence.ClassificationQuery;
+import org.taskana.persistence.ObjectReferenceQuery;
 
 /**
  * Integration Test for TaskServiceImpl transactions.
@@ -83,4 +89,38 @@ public class TaskServiceImplTransactionTest {
         Assert.assertNotNull(task);
         Assert.assertNotNull(task.getId());
     }
+
+    @Test
+    public void should_ReturnList_when_BuilderIsUsed() throws SQLException, NotAuthorizedException {
+        JdbcDataSource ds = new JdbcDataSource();
+        ds.setURL("jdbc:h2:~/data/test-db-taskservice-int2");
+        ds.setPassword("sa");
+        ds.setUser("sa");
+        TaskanaEngineConfiguration taskanaEngineConfiguration = new TaskanaEngineConfiguration(ds, true, false);
+
+        TaskanaEngineImpl te = (TaskanaEngineImpl) taskanaEngineConfiguration.buildTaskanaEngine();
+        TaskServiceImpl taskServiceImpl = (TaskServiceImpl) te.getTaskService();
+
+        Task task = new Task();
+        task.setName("Unit Test Task");
+        task.setWorkbasketId("1");
+        task = taskServiceImpl.create(task);
+
+        ClassificationQuery classificationQuery = new ClassificationQueryImpl(te).tenantId("asdasdasd")
+                .parentClassification("pId1", "pId2").category("cat1", "cat2").type("oneType").name("1Name", "name2")
+                .descriptionLike("my desc").priority(1, 2, 1).serviceLevel("me", "and", "you");
+
+        ObjectReferenceQuery objectReferenceQuery = new ObjectReferenceQueryImpl(te).tenantId("tenant1")
+                .company("first comp", "sonstwo gmbh").system("sys").type("type1", "type2")
+                .systemInstance("sysInst1", "sysInst2").value("val1", "val2", "val3");
+
+        List<Task> results = taskServiceImpl.createTaskQuery().tenantId("1").name("bla", "test").descriptionLike("test")
+                .priority(1, 2, 2).state(TaskState.CLAIMED).workbasketId("asd", "asdasdasd")
+                .owner("test", "test2", "bla").customFields("test").classification(classificationQuery)
+                .objectReference(objectReferenceQuery).list();
+
+        Assert.assertEquals(0, results.size());
+
+    }
+
 }
diff --git a/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ClassificationQueryImplTest.java b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ClassificationQueryImplTest.java
new file mode 100644
index 000000000..0c50fbc5b
--- /dev/null
+++ b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ClassificationQueryImplTest.java
@@ -0,0 +1,69 @@
+package org.taskana.impl.persistence;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.when;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.ibatis.session.SqlSession;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.Classification;
+
+/**
+ * Test for ClassificationQueryImpl.
+ * @author EH
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class ClassificationQueryImplTest {
+
+    ClassificationQueryImpl classificationQueryImpl;
+
+    @Mock
+    TaskanaEngineImpl taskanaEngine;
+
+    @Mock
+    SqlSession sqlSession;
+
+    @Before
+    public void setup() {
+        classificationQueryImpl = new ClassificationQueryImpl(taskanaEngine);
+    }
+
+    @Test
+    public void should_ReturnList_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any())).thenReturn(new ArrayList<>());
+
+        List<Classification> result = classificationQueryImpl.name("test", "asd", "blubber").type("cool", "bla").priority(1, 2)
+                .parentClassification("superId").list();
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnListWithOffset_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any(), any())).thenReturn(new ArrayList<>());
+
+        List<Classification> result = classificationQueryImpl.name("test", "asd", "blubber").type("cool", "bla").priority(1, 2)
+                .parentClassification("superId").list(1, 1);
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnOneItem_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectOne(any(), any())).thenReturn(new Classification());
+
+        Classification result = classificationQueryImpl.name("test", "asd", "blubber").type("cool", "bla").priority(1, 2)
+                .parentClassification("superId").single();
+        Assert.assertNotNull(result);
+    }
+}
diff --git a/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ObjectReferenceQueryImplTest.java b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ObjectReferenceQueryImplTest.java
new file mode 100644
index 000000000..e06c7906c
--- /dev/null
+++ b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/ObjectReferenceQueryImplTest.java
@@ -0,0 +1,69 @@
+package org.taskana.impl.persistence;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.when;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.ibatis.session.SqlSession;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.ObjectReference;
+
+/**
+ * Test for ObjectReferenceQueryImpl.
+ * @author EH
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class ObjectReferenceQueryImplTest {
+
+    ObjectReferenceQueryImpl objectReferenceQueryImpl;
+
+    @Mock
+    TaskanaEngineImpl taskanaEngine;
+
+    @Mock
+    SqlSession sqlSession;
+
+    @Before
+    public void setup() {
+        objectReferenceQueryImpl = new ObjectReferenceQueryImpl(taskanaEngine);
+    }
+
+    @Test
+    public void should_ReturnList_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any())).thenReturn(new ArrayList<>());
+
+        List<ObjectReference> result = objectReferenceQueryImpl.value("test", "asd", "blubber").type("cool", "bla")
+                .systemInstance("1", "2").system("superId").list();
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnListWithOffset_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any(), any())).thenReturn(new ArrayList<>());
+
+        List<ObjectReference> result = objectReferenceQueryImpl.value("test", "asd", "blubber").type("cool", "bla")
+                .systemInstance("1", "2").system("superId").list(1, 1);
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnOneItem_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectOne(any(), any())).thenReturn(new ObjectReference());
+
+        ObjectReference result = objectReferenceQueryImpl.value("test", "asd", "blubber").type("cool", "bla")
+                .systemInstance("1", "2").system("superId").single();
+        Assert.assertNotNull(result);
+    }
+}
diff --git a/lib/taskana-core/src/test/java/org/taskana/impl/persistence/TaskQueryImplTest.java b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/TaskQueryImplTest.java
new file mode 100644
index 000000000..e98ca019d
--- /dev/null
+++ b/lib/taskana-core/src/test/java/org/taskana/impl/persistence/TaskQueryImplTest.java
@@ -0,0 +1,70 @@
+package org.taskana.impl.persistence;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.when;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.ibatis.session.SqlSession;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.impl.TaskanaEngineImpl;
+import org.taskana.model.Task;
+import org.taskana.model.TaskState;
+
+/**
+ * Test for TaskQueryImpl.
+ * @author EH
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class TaskQueryImplTest {
+
+    TaskQueryImpl taskQueryImpl;
+
+    @Mock
+    TaskanaEngineImpl taskanaEngine;
+
+    @Mock
+    SqlSession sqlSession;
+
+    @Before
+    public void setup() {
+        taskQueryImpl = new TaskQueryImpl(taskanaEngine);
+    }
+
+    @Test
+    public void should_ReturnList_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any())).thenReturn(new ArrayList<>());
+
+        List<Task> result = taskQueryImpl.name("test", "asd", "blubber").customFields("cool", "bla").priority(1, 2)
+                .state(TaskState.CLAIMED, TaskState.COMPLETED).list();
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnListWithOffset_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectList(any(), any(), any())).thenReturn(new ArrayList<>());
+
+        List<Task> result = taskQueryImpl.name("test", "asd", "blubber").customFields("cool", "bla").priority(1, 2)
+                .state(TaskState.CLAIMED, TaskState.COMPLETED).list(1, 1);
+        Assert.assertNotNull(result);
+    }
+
+    @Test
+    public void should_ReturnOneItem_when_BuilderIsUsed() throws NotAuthorizedException {
+        when(taskanaEngine.getSession()).thenReturn(sqlSession);
+        when(sqlSession.selectOne(any(), any())).thenReturn(new Task());
+
+        Task result = taskQueryImpl.name("test", "asd", "blubber").customFields("cool", "bla").priority(1, 2)
+                .state(TaskState.CLAIMED, TaskState.COMPLETED).single();
+        Assert.assertNotNull(result);
+    }
+}
diff --git a/rest/src/main/java/org/taskana/rest/TaskController.java b/rest/src/main/java/org/taskana/rest/TaskController.java
index e1583d6e1..ed34d3c67 100644
--- a/rest/src/main/java/org/taskana/rest/TaskController.java
+++ b/rest/src/main/java/org/taskana/rest/TaskController.java
@@ -1,7 +1,5 @@
 package org.taskana.rest;
 
-import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 import javax.security.auth.login.LoginException;
@@ -23,113 +21,87 @@ import org.taskana.TaskService;
 import org.taskana.exceptions.NotAuthorizedException;
 import org.taskana.exceptions.TaskNotFoundException;
 import org.taskana.model.Task;
-import org.taskana.model.TaskState;
+import org.taskana.rest.query.TaskFilter;
 
 @RestController
 @RequestMapping(path = "/v1/tasks", produces = { MediaType.APPLICATION_JSON_VALUE })
 public class TaskController {
 
-	private static final Logger logger = LoggerFactory.getLogger(TaskController.class);
+    private static final Logger logger = LoggerFactory.getLogger(TaskController.class);
 
-	@Autowired
-	private TaskService taskService;
+    @Autowired
+    private TaskService taskService;
+    @Autowired
+    private TaskFilter taskLogic;
 
-	@RequestMapping
-	public ResponseEntity<List<Task>> getTasks(@RequestParam MultiValueMap<String, String> params)
-			throws LoginException {
-		try {
-			if (params.keySet().size() == 0) {
-				return ResponseEntity.status(HttpStatus.OK).body(taskService.getTasks());
-			}
-			if (params.containsKey("workbasketid") && params.containsKey("states")) {
-				List<TaskState> states = extractStates(params);
-				return ResponseEntity.status(HttpStatus.OK)
-						.body(taskService.getTasksForWorkbasket(params.get("workbasketid"), states));
-			}
-			if (params.containsKey("states")) {
-				List<TaskState> states = extractStates(params);
-				return ResponseEntity.status(HttpStatus.OK).body(taskService.findTasks(states));
-			}
-			return ResponseEntity.status(HttpStatus.OK)
-					.body(taskService.getTasksForWorkbasket(params.getFirst("workbasketid")));
-		} catch (NotAuthorizedException e) {
-			return ResponseEntity.status(HttpStatus.UNAUTHORIZED).build();
-		}
-	}
+    @RequestMapping
+    public ResponseEntity<List<Task>> getTasks(@RequestParam MultiValueMap<String, String> params)
+            throws LoginException {
+        try {
+            if (params.keySet().size() == 0) {
+                // get all
+                return ResponseEntity.status(HttpStatus.OK).body(taskLogic.getAll());
+            }
 
-	private List<TaskState> extractStates(MultiValueMap<String, String> params) {
-		List<TaskState> states = new ArrayList<>();
-		params.get("states").stream().forEach(item -> {
-			for (String state : Arrays.asList(item.split(","))) {
-				switch (state) {
-				case "READY":
-					states.add(TaskState.READY);
-					break;
-				case "COMPLETED":
-					states.add(TaskState.COMPLETED);
-					break;
-				case "CLAIMED":
-					states.add(TaskState.CLAIMED);
-					break;
-				}
-			}
-		});
-		return states;
-	}
+            return ResponseEntity.status(HttpStatus.OK).body(taskLogic.inspectPrams(params));
+        } catch (NotAuthorizedException e) {
+            return ResponseEntity.status(HttpStatus.UNAUTHORIZED).build();
+        }
+    }
 
-	@RequestMapping(value = "/{taskId}")
-	public ResponseEntity<Task> getTask(@PathVariable(value = "taskId") String taskId) {
-		try {
-			Task task = taskService.getTaskById(taskId);
-			return ResponseEntity.status(HttpStatus.OK).body(task);
-		} catch (TaskNotFoundException e) {
-			return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
-		}
-	}
+    @RequestMapping(value = "/{taskId}")
+    public ResponseEntity<Task> getTask(@PathVariable(value = "taskId") String taskId) {
+        try {
+            Task task = taskService.getTaskById(taskId);
+            return ResponseEntity.status(HttpStatus.OK).body(task);
+        } catch (TaskNotFoundException e) {
+            return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
+        }
+    }
 
-	@RequestMapping(method = RequestMethod.POST, value = "/{taskId}/claim")
-	public ResponseEntity<Task> claimTask(@PathVariable String taskId, @RequestBody String userName) {
-		// TODO verify user
-		try {
-			taskService.claim(taskId, userName);
-			Task updatedTask = taskService.getTaskById(taskId);
-			return ResponseEntity.status(HttpStatus.OK).body(updatedTask);
-		} catch (TaskNotFoundException e) {
-			return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
-		}
-	}
+    @RequestMapping(method = RequestMethod.POST, value = "/{taskId}/claim")
+    public ResponseEntity<Task> claimTask(@PathVariable String taskId, @RequestBody String userName) {
+        // TODO verify user
+        try {
+            taskService.claim(taskId, userName);
+            Task updatedTask = taskService.getTaskById(taskId);
+            return ResponseEntity.status(HttpStatus.OK).body(updatedTask);
+        } catch (TaskNotFoundException e) {
+            return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
+        }
+    }
 
-	@RequestMapping(method = RequestMethod.POST, value = "/{taskId}/complete")
-	public ResponseEntity<Task> completeTask(@PathVariable String taskId) {
-		try {
-			taskService.complete(taskId);
-			Task updatedTask = taskService.getTaskById(taskId);
-			return ResponseEntity.status(HttpStatus.OK).body(updatedTask);
-		} catch (TaskNotFoundException e) {
-			return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
-		}
-	}
+    @RequestMapping(method = RequestMethod.POST, value = "/{taskId}/complete")
+    public ResponseEntity<Task> completeTask(@PathVariable String taskId) {
+        try {
+            taskService.complete(taskId);
+            Task updatedTask = taskService.getTaskById(taskId);
+            return ResponseEntity.status(HttpStatus.OK).body(updatedTask);
+        } catch (TaskNotFoundException e) {
+            return ResponseEntity.status(HttpStatus.NOT_FOUND).build();
+        }
+    }
 
-	@RequestMapping(method = RequestMethod.POST)
-	public ResponseEntity<Task> createTask(@RequestBody Task task) {
-		try {
-			Task createdTask = taskService.create(task);
-			return ResponseEntity.status(HttpStatus.CREATED).body(createdTask);
-		} catch (Exception e) {
-			logger.error("Something went wrong: ", e);
-			return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
-		}
-	}
+    @RequestMapping(method = RequestMethod.POST)
+    public ResponseEntity<Task> createTask(@RequestBody Task task) {
+        try {
+            Task createdTask = taskService.create(task);
+            return ResponseEntity.status(HttpStatus.CREATED).body(createdTask);
+        } catch (Exception e) {
+            logger.error("Something went wrong: ", e);
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
+        }
+    }
 
-	@RequestMapping(method = RequestMethod.POST, value = "/{taskId}/transfer/{workbasketId}")
-	public ResponseEntity<Task> transferTask(@PathVariable String taskId, @PathVariable String workbasketId) {
-		try {
-			Task updatedTask = taskService.transfer(taskId, workbasketId);
-			return ResponseEntity.status(HttpStatus.CREATED).body(updatedTask);
-		} catch (Exception e) {
-			logger.error("Something went wrong: ", e);
-			return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
-		}
-	}
+    @RequestMapping(method = RequestMethod.POST, value = "/{taskId}/transfer/{workbasketId}")
+    public ResponseEntity<Task> transferTask(@PathVariable String taskId, @PathVariable String workbasketId) {
+        try {
+            Task updatedTask = taskService.transfer(taskId, workbasketId);
+            return ResponseEntity.status(HttpStatus.CREATED).body(updatedTask);
+        } catch (Exception e) {
+            logger.error("Something went wrong: ", e);
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
+        }
+    }
 
 }
diff --git a/rest/src/main/java/org/taskana/rest/query/TaskFilter.java b/rest/src/main/java/org/taskana/rest/query/TaskFilter.java
new file mode 100644
index 000000000..fc071a930
--- /dev/null
+++ b/rest/src/main/java/org/taskana/rest/query/TaskFilter.java
@@ -0,0 +1,214 @@
+package org.taskana.rest.query;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+import org.springframework.util.MultiValueMap;
+import org.taskana.ClassificationService;
+import org.taskana.TaskService;
+import org.taskana.exceptions.NotAuthorizedException;
+import org.taskana.model.Task;
+import org.taskana.model.TaskState;
+import org.taskana.persistence.ClassificationQuery;
+import org.taskana.persistence.ObjectReferenceQuery;
+import org.taskana.persistence.TaskQuery;
+
+@Component
+public class TaskFilter {
+
+    private static final String CLASSIFICATION = "classification";
+    private static final String POR = "por";
+    private static final String DOT = ".";
+
+    private static final String STATE = "state";
+    private static final String PRIORITY = "priority";
+    private static final String DESCRIPTION = "description";
+    private static final String TENANT_ID = "tenantId";
+    private static final String NAME = "name";
+    private static final String OWNER = "owner";
+    private static final String WORKBASKET_ID = "workbasketId";
+    private static final String CUSTOM = "custom";
+    private static final String IS_TRANSFERRED = "isTransferred";
+    private static final String IS_READ = "isRead";
+
+    private static final String CLASSIFICATION_TENANT_ID = CLASSIFICATION + DOT + "tenantId";
+    private static final String CLASSIFICATION_SERVICE_LEVEL = CLASSIFICATION + DOT + "serviceLevel";
+    private static final String CLASSIFICATION_PRIORITY = CLASSIFICATION + DOT + "priority";
+    private static final String CLASSIFICATION_DESCRIPTION = CLASSIFICATION + DOT + "description";
+    private static final String CLASSIFICATION_NAME = CLASSIFICATION + DOT + "name";
+    private static final String CLASSIFICATION_TYPE = CLASSIFICATION + DOT + "type";
+    private static final String CLASSIFICATION_CATEGORY = CLASSIFICATION + DOT + "category";
+    private static final String CLASSIFICATION_PARENT_ID = CLASSIFICATION + DOT + "parentClassificationId";
+
+    private static final String POR_VALUE = POR + DOT + "value";
+    private static final String POR_TYPE = POR + DOT + "type";
+    private static final String POR_SYSTEM_INSTANCE = POR + DOT + "systemInstance";
+    private static final String POR_SYSTEM = POR + DOT + "system";
+    private static final String POR_COMPANY = POR + DOT + "company";
+    private static final String POR_TENANT_ID = POR + DOT + "tenantId";
+
+    private static final String CLAIMED = "CLAIMED";
+    private static final String COMPLETED = "COMPLETED";
+    private static final String READY = "READY";
+    private static final String COMMA = ",";
+
+    @Autowired
+    private TaskService taskService;
+
+    @Autowired
+    private ClassificationService classificationService;
+
+    public List<Task> getAll() throws NotAuthorizedException {
+        return taskService.createTaskQuery().list();
+    }
+
+    public List<Task> inspectPrams(MultiValueMap<String, String> params) throws NotAuthorizedException {
+        TaskQuery taskQuery = taskService.createTaskQuery();
+
+        // apply filters
+        if (params.containsKey(TENANT_ID)) {
+            taskQuery.workbasketId(params.get(TENANT_ID).toArray(new String[0]));
+        }
+        if (params.containsKey(NAME)) {
+            String[] names = extractCommaSeperatedFields(params.get(NAME));
+            taskQuery.name(names);
+        }
+        if (params.containsKey(DESCRIPTION)) {
+            taskQuery.descriptionLike(params.get(DESCRIPTION).get(0));
+        }
+        if (params.containsKey(PRIORITY)) {
+            String[] prioritesInString = extractCommaSeperatedFields(params.get(PRIORITY));
+            int[] priorites = extractPriorities(prioritesInString);
+            taskQuery.priority(priorites);
+        }
+        if (params.containsKey(STATE)) {
+            TaskState[] states = extractStates(params);
+            taskQuery.state(states);
+        }
+        // classification
+        if (params.keySet().stream().filter(s -> s.startsWith(CLASSIFICATION)).toArray().length > 0) {
+            ClassificationQuery classificationQuery = classificationService.createClassificationQuery();
+            if (params.containsKey(CLASSIFICATION_TENANT_ID)) {
+                classificationQuery.tenantId(params.get(CLASSIFICATION_TENANT_ID).get(0));
+            }
+            if (params.containsKey(CLASSIFICATION_PARENT_ID)) {
+                String[] parentClassifications = extractCommaSeperatedFields(params.get(CLASSIFICATION_PARENT_ID));
+                classificationQuery.parentClassification(parentClassifications);
+            }
+            if (params.containsKey(CLASSIFICATION_CATEGORY)) {
+                String[] categories = extractCommaSeperatedFields(params.get(CLASSIFICATION_CATEGORY));
+                classificationQuery.category(categories);
+            }
+            if (params.containsKey(CLASSIFICATION_TYPE)) {
+                String[] types = extractCommaSeperatedFields(params.get(CLASSIFICATION_TYPE));
+                classificationQuery.type(types);
+            }
+            if (params.containsKey(CLASSIFICATION_NAME)) {
+                String[] names = extractCommaSeperatedFields(params.get(CLASSIFICATION_NAME));
+                classificationQuery.name(names);
+            }
+            if (params.containsKey(CLASSIFICATION_DESCRIPTION)) {
+                classificationQuery.descriptionLike(params.get(CLASSIFICATION_DESCRIPTION).get(0));
+            }
+            if (params.containsKey(CLASSIFICATION_PRIORITY)) {
+                String[] prioritesInString = extractCommaSeperatedFields(params.get(CLASSIFICATION_PRIORITY));
+                int[] priorites = extractPriorities(prioritesInString);
+                classificationQuery.priority(priorites);
+            }
+            if (params.containsKey(CLASSIFICATION_SERVICE_LEVEL)) {
+                String[] serviceLevels = extractCommaSeperatedFields(params.get(CLASSIFICATION_SERVICE_LEVEL));
+                classificationQuery.serviceLevel(serviceLevels);
+            }
+            taskQuery.classification(classificationQuery);
+        }
+        if (params.containsKey(WORKBASKET_ID)) {
+            String[] workbaskets = extractCommaSeperatedFields(params.get(WORKBASKET_ID));
+            taskQuery.workbasketId(workbaskets);
+        }
+        if (params.containsKey(OWNER)) {
+            String[] owners = extractCommaSeperatedFields(params.get(OWNER));
+            taskQuery.owner(owners);
+        }
+        // objectReference
+        if (params.keySet().stream().filter(s -> s.startsWith(POR)).toArray().length > 0) {
+            ObjectReferenceQuery objectReferenceQuery = taskQuery.createObjectReferenceQuery();
+            if (params.containsKey(POR_TENANT_ID)) {
+                objectReferenceQuery.tenantId(params.get(POR_TENANT_ID).get(0));
+            }
+            if (params.containsKey(POR_COMPANY)) {
+                String[] companies = extractCommaSeperatedFields(params.get(POR_COMPANY));
+                objectReferenceQuery.company(companies);
+            }
+            if (params.containsKey(POR_SYSTEM)) {
+                String[] systems = extractCommaSeperatedFields(params.get(POR_SYSTEM));
+                objectReferenceQuery.system(systems);
+            }
+            if (params.containsKey(POR_SYSTEM_INSTANCE)) {
+                String[] systemInstances = extractCommaSeperatedFields(params.get(POR_SYSTEM_INSTANCE));
+                objectReferenceQuery.systemInstance(systemInstances);
+            }
+            if (params.containsKey(POR_TYPE)) {
+                String[] types = extractCommaSeperatedFields(params.get(POR_TYPE));
+                objectReferenceQuery.type(types);
+            }
+            if (params.containsKey(POR_VALUE)) {
+                String[] values = extractCommaSeperatedFields(params.get(POR_VALUE));
+                objectReferenceQuery.value(values);
+            }
+
+            taskQuery.objectReference(objectReferenceQuery);
+        }
+        if (params.containsKey(IS_READ)) {
+            taskQuery.read(Boolean.getBoolean(params.get(IS_READ).get(0)));
+        }
+        if (params.containsKey(IS_TRANSFERRED)) {
+            taskQuery.transferred(Boolean.getBoolean(params.get(IS_TRANSFERRED).get(0)));
+        }
+        if (params.containsKey(CUSTOM)) {
+            String[] custom = extractCommaSeperatedFields(params.get(CUSTOM));
+            taskQuery.customFields(custom);
+        }
+        return taskQuery.list();
+    }
+
+    private int[] extractPriorities(String[] prioritesInString) {
+        int[] priorites = new int[prioritesInString.length];
+        for (int i = 0; i < prioritesInString.length; i++) {
+            priorites[i] = Integer.getInteger(prioritesInString[i]);
+        }
+        return priorites;
+    }
+
+    private String[] extractCommaSeperatedFields(List<String> list) {
+        List<String> values = new ArrayList<>();
+        list.stream().forEach(item -> {
+            Arrays.asList(item.split(COMMA)).stream().forEach(subItem -> {
+                values.add(subItem);
+            });
+        });
+        return values.toArray(new String[0]);
+    }
+
+    private TaskState[] extractStates(MultiValueMap<String, String> params) {
+        List<TaskState> states = new ArrayList<>();
+        params.get(STATE).stream().forEach(item -> {
+            Arrays.asList(item.split(COMMA)).stream().forEach(state -> {
+                switch (state) {
+                case READY:
+                    states.add(TaskState.READY);
+                    break;
+                case COMPLETED:
+                    states.add(TaskState.COMPLETED);
+                    break;
+                case CLAIMED:
+                    states.add(TaskState.CLAIMED);
+                    break;
+                }
+            });
+        });
+        return states.toArray(new TaskState[0]);
+    }
+}