diff --git a/repository/OpenPonk-BormEditor/OPBormActivityControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormActivityControllerTest.class.st
index 2ac7853..75efe0a 100644
--- a/repository/OpenPonk-BormEditor/OPBormActivityControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormActivityControllerTest.class.st
@@ -3,7 +3,7 @@ A BormActivityControllerTest is a test class for testing the behavior of BormAct
 "
 Class {
 	#name : 'OPBormActivityControllerTest',
-	#superclass : 'OPBormControllerTest',
+	#superclass : 'OPBormProcessNodeControllerTest',
 	#category : 'OpenPonk-BormEditor-Tests',
 	#package : 'OpenPonk-BormEditor',
 	#tag : 'Tests'
@@ -15,21 +15,21 @@ OPBormActivityControllerTest >> controllerClass [
 ]
 
 { #category : 'accessing' }
-OPBormActivityControllerTest >> diagramElementClass [
-	^ BormActivityShape
+OPBormActivityControllerTest >> creationTargetControllerClass [
+	^ OPBormParticipantController
 ]
 
 { #category : 'accessing' }
-OPBormActivityControllerTest >> modelClass [
-	^ BormActivity
+OPBormActivityControllerTest >> creationTargetModelClass [
+	^ BormParticipant
 ]
 
 { #category : 'accessing' }
-OPBormActivityControllerTest >> targetControllerClass [
-	^ OPBormParticipantController
+OPBormActivityControllerTest >> diagramElementClass [
+	^ BormActivityShape
 ]
 
 { #category : 'accessing' }
-OPBormActivityControllerTest >> targetModelClass [
-	^ BormParticipant
+OPBormActivityControllerTest >> modelClass [
+	^ BormActivity
 ]
diff --git a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
index 195d1a5..e8ad043 100644
--- a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
@@ -6,6 +6,14 @@ Class {
 	#tag : 'Controllers'
 }
 
+{ #category : 'construction' }
+OPBormAssociationEnhancementController >> dependingOnElements [
+
+	^ super dependingOnElements , (Set with:
+		   (self model owner ifNil: [
+			    self error: 'There is no owner of ' , self model asString ]))
+]
+
 { #category : 'diagram elements' }
 OPBormAssociationEnhancementController >> diagramElementOwner [
 
diff --git a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementControllerTest.class.st
index 749cd66..525953d 100644
--- a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementControllerTest.class.st
@@ -1,10 +1,6 @@
 Class {
 	#name : 'OPBormAssociationEnhancementControllerTest',
-	#superclass : 'OPBormControllerTest',
-	#instVars : [
-		'relationshipsSourceController',
-		'relationshipsTargetController'
-	],
+	#superclass : 'OPBormElementControllerTest',
 	#category : 'OpenPonk-BormEditor-Tests',
 	#package : 'OpenPonk-BormEditor',
 	#tag : 'Tests'
@@ -16,36 +12,40 @@ OPBormAssociationEnhancementControllerTest class >> isAbstract [
 	^ self = OPBormAssociationEnhancementControllerTest
 ]
 
-{ #category : 'initialization' }
-OPBormAssociationEnhancementControllerTest >> setUpTarget [
-
-	relationshipsSourceController := self targetsSourceControllerClass
-		                                 new.
-	relationshipsSourceController diagramController: diagramController.
-	relationshipsSourceController createModelIn: diagramController model.
-	relationshipsTargetController := OPBormActivityController new.
-	relationshipsTargetController diagramController: diagramController.
-	relationshipsTargetController createModelIn: diagramController model.
-	relationshipController := self targetControllerClass new.
-	relationshipController diagramController: diagramController.
-	relationshipController
-		source: relationshipsTargetController;
-		target: relationshipsSourceController.
-	relationshipController createModelIn:
-		relationshipsSourceController model
-]
-
-{ #category : 'running' }
-OPBormAssociationEnhancementControllerTest >> targetsSourceControllerClass [
+{ #category : 'accessing' }
+OPBormAssociationEnhancementControllerTest >> creationTargetControllerClass [
 
-	^ self subclassResponsibility
+	^ OPBormCommunicationController
 ]
 
-{ #category : 'tests' }
-OPBormAssociationEnhancementControllerTest >> testCreateDiagramElement [
+{ #category : 'accessing' }
+OPBormAssociationEnhancementControllerTest >> creationTargetModelClass [
 
-	relationshipController model add: model.
-	diagramController addController: relationshipController.
+	^ BormCommunication
+]
 
-	super testCreateDiagramElement
+{ #category : 'accessing' }
+OPBormAssociationEnhancementControllerTest >> setUpCreationTargetModel [
+
+	| sourceParticipant targetParticipant sourceActivity targetActivity creationTargetModel |
+	sourceParticipant := BormParticipant new.
+	diagramController model add: sourceParticipant.
+	targetParticipant := BormParticipant new.
+	diagramController model add: targetParticipant.
+
+	sourceActivity := BormActivity new.
+	sourceParticipant add: sourceActivity.
+
+	targetActivity := BormActivity new.
+	targetParticipant add: targetActivity.
+
+	creationTargetModel := self creationTargetModelClass new.
+	creationTargetController model: creationTargetModel.
+	creationTargetController
+		modelSource: sourceActivity
+		in: targetActivity.
+	creationTargetController
+		modelTarget: targetActivity
+		in: targetActivity.
+	^ creationTargetModel
 ]
diff --git a/repository/OpenPonk-BormEditor/OPBormCommunicationController.class.st b/repository/OpenPonk-BormEditor/OPBormCommunicationController.class.st
index 25de4be..a028eb7 100644
--- a/repository/OpenPonk-BormEditor/OPBormCommunicationController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormCommunicationController.class.st
@@ -11,16 +11,6 @@ OPBormCommunicationController >> canBeTargetForDataFlow: aController [
 	^ true
 ]
 
-{ #category : 'accessing' }
-OPBormCommunicationController >> createModelIn: aParentModel [
-	self model: self modelClass new.
-	model source: self source model.
-	model target: self target model.
-	source model send: model.
-	target model receive: model.
-	^ model
-]
-
 { #category : 'construction' }
 OPBormCommunicationController >> diagramElementClass [
 
@@ -37,6 +27,22 @@ OPBormCommunicationController >> modelClass [
 	^ BormCommunication
 ]
 
+{ #category : 'accessing' }
+OPBormCommunicationController >> modelSource: aModel in: aParentModel [
+
+	(super modelSource: aModel in: aParentModel) ifFalse: [ ^ false ].
+	self modelSource send: model.
+	^ true
+]
+
+{ #category : 'accessing' }
+OPBormCommunicationController >> modelTarget: aModel in: aParentModel [
+
+	(super modelTarget: aModel in: aParentModel) ifFalse: [ ^ false ].
+	self modelTarget receive: model.
+	^ true
+]
+
 { #category : 'destruction' }
 OPBormCommunicationController >> removeModel [
 	self model target removeCommunication: self model.
diff --git a/repository/OpenPonk-BormEditor/OPBormCommunicationControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormCommunicationControllerTest.class.st
index 22049f4..0586e94 100644
--- a/repository/OpenPonk-BormEditor/OPBormCommunicationControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormCommunicationControllerTest.class.st
@@ -9,6 +9,20 @@ Class {
 	#tag : 'Tests'
 }
 
+{ #category : 'initialization' }
+OPBormCommunicationControllerTest >> assignModelSource [
+
+	super assignModelSource.
+	model source send: model
+]
+
+{ #category : 'initialization' }
+OPBormCommunicationControllerTest >> assignModelTarget [
+
+	super assignModelTarget.
+	model target receive: model
+]
+
 { #category : 'accessing' }
 OPBormCommunicationControllerTest >> controllerClass [
 	^ OPBormCommunicationController
@@ -26,6 +40,12 @@ OPBormCommunicationControllerTest >> modelClass [
 ]
 
 { #category : 'as yet unclassified' }
-OPBormCommunicationControllerTest >> targetControllerClass [
+OPBormCommunicationControllerTest >> sourceControllerClass [
 	^ OPBormActivityController
 ]
+
+{ #category : 'as yet unclassified' }
+OPBormCommunicationControllerTest >> sourceModelClass [
+
+	^ BormActivity
+]
diff --git a/repository/OpenPonk-BormEditor/OPBormConstraintController.class.st b/repository/OpenPonk-BormEditor/OPBormConstraintController.class.st
index 83092a7..0f7842a 100644
--- a/repository/OpenPonk-BormEditor/OPBormConstraintController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormConstraintController.class.st
@@ -11,14 +11,6 @@ OPBormConstraintController >> canVisitTarget: aController [
 	^ aController canBeTargetForConstraint: self
 ]
 
-{ #category : 'construction' }
-OPBormConstraintController >> createModelIn: aParentModel [
-
-	self model: self modelClass new.
-	aParentModel constraint: model.
-	^ model
-]
-
 { #category : 'construction' }
 OPBormConstraintController >> diagramElementClass [
 
@@ -30,6 +22,12 @@ OPBormConstraintController >> modelClass [
 	^ BormConstraint
 ]
 
+{ #category : 'construction' }
+OPBormConstraintController >> registerModelInContainer: aParentModel [
+
+	aParentModel constraint: model
+]
+
 { #category : 'private' }
 OPBormConstraintController >> removeModel [
 
diff --git a/repository/OpenPonk-BormEditor/OPBormConstraintControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormConstraintControllerTest.class.st
index b385a52..f6f5bfb 100644
--- a/repository/OpenPonk-BormEditor/OPBormConstraintControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormConstraintControllerTest.class.st
@@ -24,19 +24,3 @@ OPBormConstraintControllerTest >> diagramElementClass [
 OPBormConstraintControllerTest >> modelClass [
 	^ BormConstraint
 ]
-
-{ #category : 'accessing' }
-OPBormConstraintControllerTest >> targetControllerClass [
-	^ OPBormTransitionController
-]
-
-{ #category : 'accessing' }
-OPBormConstraintControllerTest >> targetModelClass [
-	^ BormTransition
-]
-
-{ #category : 'running' }
-OPBormConstraintControllerTest >> targetsSourceControllerClass [
-
-	^ OPBormStateController
-]
diff --git a/repository/OpenPonk-BormEditor/OPBormContainerControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormContainerControllerTest.class.st
index eda374b..fdc0ec9 100644
--- a/repository/OpenPonk-BormEditor/OPBormContainerControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormContainerControllerTest.class.st
@@ -1,6 +1,6 @@
 Class {
 	#name : 'OPBormContainerControllerTest',
-	#superclass : 'OPBormControllerTest',
+	#superclass : 'OPBormElementControllerTest',
 	#category : 'OpenPonk-BormEditor-Tests',
 	#package : 'OpenPonk-BormEditor',
 	#tag : 'Tests'
diff --git a/repository/OpenPonk-BormEditor/OPBormControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormControllerTest.class.st
deleted file mode 100644
index 384c3d2..0000000
--- a/repository/OpenPonk-BormEditor/OPBormControllerTest.class.st
+++ /dev/null
@@ -1,101 +0,0 @@
-Class {
-	#name : 'OPBormControllerTest',
-	#superclass : 'OPElementControllerTest',
-	#instVars : [
-		'relationshipController'
-	],
-	#category : 'OpenPonk-BormEditor-Tests',
-	#package : 'OpenPonk-BormEditor',
-	#tag : 'Tests'
-}
-
-{ #category : 'testing' }
-OPBormControllerTest class >> isAbstract [
-	"Override to true if a TestCase subclass is Abstract and should not have
-	TestCase instances built from it"
-
-	^ self = OPBormControllerTest
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> controllerClass [
-	^ self subclassResponsibility
-]
-
-{ #category : 'running' }
-OPBormControllerTest >> createTargetController [
-	^ self targetControllerClass new
-		model: self createTargetModel;
-		yourself
-]
-
-{ #category : 'running' }
-OPBormControllerTest >> createTargetModel [
-	^ self targetModelClass new
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> diagramControllerClass [
-
-	^ OPBormDiagramController
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> diagramModelClass [
-	^ BormORModel
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> modelClass [
-	^ self subclassResponsibility
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> modelOwner [
-	^ diagramController model
-]
-
-{ #category : 'running' }
-OPBormControllerTest >> setUp [
-	super setUp.
-	self setUpTarget
-]
-
-{ #category : 'running' }
-OPBormControllerTest >> setUpTarget [
-	relationshipController := self targetControllerClass new.
-	relationshipController diagramController: diagramController.
-	relationshipController createModelIn: diagramController model
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> targetControllerClass [
-	^ self subclassResponsibility
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> targetModelClass [
-	^ self subclassResponsibility
-]
-
-{ #category : 'tests' }
-OPBormControllerTest >> testAssignmentToParent [
-	controller createModelIn: relationshipController model.
-	self assert: (relationshipController model has: controller model)
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> testCreateController [
-	self assert: controller class = self controllerClass
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> testCreateModel [
-	controller createModelIn: relationshipController model.
-	self assert: controller model class equals: self modelClass
-]
-
-{ #category : 'accessing' }
-OPBormControllerTest >> testModelClass [
-	self assert: controller modelClass equals: self modelClass
-]
diff --git a/repository/OpenPonk-BormEditor/OPBormDataFlowController.class.st b/repository/OpenPonk-BormEditor/OPBormDataFlowController.class.st
index b8a105d..e4b4cc5 100644
--- a/repository/OpenPonk-BormEditor/OPBormDataFlowController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormDataFlowController.class.st
@@ -28,14 +28,6 @@ OPBormDataFlowController >> canVisitTarget: aController [
 	^ aController canBeTargetForDataFlow: self
 ]
 
-{ #category : 'construction' }
-OPBormDataFlowController >> createModelIn: aParentModel [
-
-	self model: self modelClass new.
-	aParentModel add: model.
-	^ model
-]
-
 { #category : 'construction' }
 OPBormDataFlowController >> diagramElementClass [
 
diff --git a/repository/OpenPonk-BormEditor/OPBormDataFlowControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormDataFlowControllerTest.class.st
index 7d926dc..08f7d94 100644
--- a/repository/OpenPonk-BormEditor/OPBormDataFlowControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormDataFlowControllerTest.class.st
@@ -28,33 +28,3 @@ OPBormDataFlowControllerTest >> diagramElementClass [
 OPBormDataFlowControllerTest >> modelClass [
 	^ BormDataFlow
 ]
-
-{ #category : 'as yet unclassified' }
-OPBormDataFlowControllerTest >> modelOwner [
-	^ communication
-]
-
-{ #category : 'running' }
-OPBormDataFlowControllerTest >> setUp [
-	super setUp.
-	communicationController := OPBormCommunicationController new.
-	communication := BormCommunication new.
-	communicationController model: communication.
-	diagramController addController: communicationController
-]
-
-{ #category : 'accessing' }
-OPBormDataFlowControllerTest >> targetControllerClass [
-	^ OPBormCommunicationController
-]
-
-{ #category : 'accessing' }
-OPBormDataFlowControllerTest >> targetModelClass [
-	^ BormCommunication
-]
-
-{ #category : 'running' }
-OPBormDataFlowControllerTest >> targetsSourceControllerClass [
-
-	^ OPBormActivityController
-]
diff --git a/repository/OpenPonk-BormEditor/OPBormDiagramController.class.st b/repository/OpenPonk-BormEditor/OPBormDiagramController.class.st
index a86ba85..43a6226 100644
--- a/repository/OpenPonk-BormEditor/OPBormDiagramController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormDiagramController.class.st
@@ -57,6 +57,7 @@ OPBormDiagramController >> controllerFactory [
 
 { #category : 'rebuilding' }
 OPBormDiagramController >> elementsToShowInside [
+
 	^ model participants
 ]
 
diff --git a/repository/OpenPonk-BormEditor/OPBormElementControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormElementControllerTest.class.st
new file mode 100644
index 0000000..608f0bf
--- /dev/null
+++ b/repository/OpenPonk-BormEditor/OPBormElementControllerTest.class.st
@@ -0,0 +1,36 @@
+Class {
+	#name : 'OPBormElementControllerTest',
+	#superclass : 'OPAbstractElementControllerTest',
+	#category : 'OpenPonk-BormEditor-Tests',
+	#package : 'OpenPonk-BormEditor',
+	#tag : 'Tests'
+}
+
+{ #category : 'testing' }
+OPBormElementControllerTest class >> isAbstract [
+	"Override to true if a TestCase subclass is Abstract and should not have
+	TestCase instances built from it"
+
+	^ self = OPBormElementControllerTest
+]
+
+{ #category : 'accessing' }
+OPBormElementControllerTest >> creationTargetControllerClass [
+	^ self subclassResponsibility
+]
+
+{ #category : 'accessing' }
+OPBormElementControllerTest >> creationTargetModelClass [
+	^ self subclassResponsibility
+]
+
+{ #category : 'accessing' }
+OPBormElementControllerTest >> diagramControllerClass [
+
+	^ OPBormDiagramController
+]
+
+{ #category : 'accessing' }
+OPBormElementControllerTest >> diagramModelClass [
+	^ BormORModel
+]
diff --git a/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st b/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
index f824fea..fd0d450 100644
--- a/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
@@ -65,7 +65,8 @@ OPBormParticipantController >> nodeRoassalShapes [
 
 { #category : 'destruction' }
 OPBormParticipantController >> removeModel [
-	self diagramController model remove: self model
+
+	self model owner remove: self model
 ]
 
 { #category : 'hooks' }
diff --git a/repository/OpenPonk-BormEditor/OPBormParticipantControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormParticipantControllerTest.class.st
index f933849..1556c63 100644
--- a/repository/OpenPonk-BormEditor/OPBormParticipantControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormParticipantControllerTest.class.st
@@ -17,8 +17,13 @@ OPBormParticipantControllerTest >> createTargetController [
 ]
 
 { #category : 'accessing' }
-OPBormParticipantControllerTest >> createTargetModel [
-	^ diagramController model
+OPBormParticipantControllerTest >> creationTargetControllerClass [
+	^ self diagramControllerClass
+]
+
+{ #category : 'accessing' }
+OPBormParticipantControllerTest >> creationTargetModelClass [
+	^ self diagramModelClass
 ]
 
 { #category : 'accessing' }
@@ -31,18 +36,3 @@ OPBormParticipantControllerTest >> diagramElementClass [
 OPBormParticipantControllerTest >> modelClass [
 	^ BormParticipant
 ]
-
-{ #category : 'running' }
-OPBormParticipantControllerTest >> setUpTarget [
-	relationshipController := diagramController
-]
-
-{ #category : 'accessing' }
-OPBormParticipantControllerTest >> targetControllerClass [
-	^ self diagramControllerClass
-]
-
-{ #category : 'accessing' }
-OPBormParticipantControllerTest >> targetModelClass [
-	^ self diagramModelClass
-]
diff --git a/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st b/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
index ba80e56..a769086 100644
--- a/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
@@ -6,15 +6,6 @@ Class {
 	#tag : 'Controllers'
 }
 
-{ #category : 'adding' }
-OPBormProcessNodeController >> addAsTargetFor: aController [
-	self assert: (self canBeTargetFor: aController).
-	aController target: self.
-	aController
-		createModelIn: self model
-		andShowInDiagram: self diagramController
-]
-
 { #category : 'adding' }
 OPBormProcessNodeController >> bormModels [
 	^ self diagramController editor workbench projectController project models
@@ -26,14 +17,15 @@ OPBormProcessNodeController >> buildEditorForm: aForm [
 
 	(aForm addText: 'Name')
 		text: self model name;
-		whenTextChangedDo: [ :newValue | 
+		whenTextChangedDo: [ :newValue |
 			self model name: newValue asString.
 			self diagramElement modelChanged ].
+	self diagramController editor ifNil: [ ^ self ].
 	(aForm addDroplist: 'Submodel')
 		items: { nil } , self bormModels;
 		display: [ :m | m ifNil: '' ifNotNil: #name ];
 		selectItem: self model submodel;
-		whenSelectedItemChangedDo: [ :newValue | 
+		whenSelectedItemChangedDo: [ :newValue |
 			self model submodel: newValue.
 			self diagramElement modelChanged ]
 ]
@@ -53,6 +45,14 @@ OPBormProcessNodeController >> dependentElements [
 	^ model transitions
 ]
 
+{ #category : 'construction' }
+OPBormProcessNodeController >> dependingOnElements [
+
+	^ super dependingOnElements
+	  , (Set with: (self model participant ifNil: [
+				    self error: 'There is no participant of ' , self model asString ]))
+]
+
 { #category : 'construction' }
 OPBormProcessNodeController >> hookDiagramElement [
 
diff --git a/repository/OpenPonk-BormEditor/OPBormProcessNodeControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormProcessNodeControllerTest.class.st
new file mode 100644
index 0000000..e6c7cd1
--- /dev/null
+++ b/repository/OpenPonk-BormEditor/OPBormProcessNodeControllerTest.class.st
@@ -0,0 +1,15 @@
+Class {
+	#name : 'OPBormProcessNodeControllerTest',
+	#superclass : 'OPBormElementControllerTest',
+	#category : 'OpenPonk-BormEditor-Tests',
+	#package : 'OpenPonk-BormEditor',
+	#tag : 'Tests'
+}
+
+{ #category : 'testing' }
+OPBormProcessNodeControllerTest class >> isAbstract [
+	"Override to true if a TestCase subclass is Abstract and should not have
+	TestCase instances built from it"
+
+	^ self = OPBormProcessNodeControllerTest
+]
diff --git a/repository/OpenPonk-BormEditor/OPBormRelationshipController.class.st b/repository/OpenPonk-BormEditor/OPBormRelationshipController.class.st
index 4efff36..fee1bbc 100644
--- a/repository/OpenPonk-BormEditor/OPBormRelationshipController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormRelationshipController.class.st
@@ -31,3 +31,9 @@ OPBormRelationshipController >> elementsToShowInside [
 OPBormRelationshipController >> isHideable [
 	^ true
 ]
+
+{ #category : 'construction' }
+OPBormRelationshipController >> registerModelInContainer: aParentModel [
+
+	"do nothing"
+]
diff --git a/repository/OpenPonk-BormEditor/OPBormRelationshipControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormRelationshipControllerTest.class.st
index d48656e..9b8bf19 100644
--- a/repository/OpenPonk-BormEditor/OPBormRelationshipControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormRelationshipControllerTest.class.st
@@ -1,9 +1,6 @@
 Class {
 	#name : 'OPBormRelationshipControllerTest',
-	#superclass : 'OPBormControllerTest',
-	#instVars : [
-		'sourceController'
-	],
+	#superclass : 'OPAbstractDirectionalRelationshipControllerTest',
 	#category : 'OpenPonk-BormEditor-Tests',
 	#package : 'OpenPonk-BormEditor',
 	#tag : 'Tests'
@@ -14,22 +11,33 @@ OPBormRelationshipControllerTest class >> isAbstract [
 	^ self = OPBormRelationshipControllerTest
 ]
 
-{ #category : 'running' }
-OPBormRelationshipControllerTest >> setUp [
-	super setUp.
-	self setUpSource.
-	controller source: sourceController.
-	controller target: relationshipController
+{ #category : 'accessing' }
+OPBormRelationshipControllerTest >> diagramControllerClass [
+
+	^ OPBormDiagramController
+]
+
+{ #category : 'accessing' }
+OPBormRelationshipControllerTest >> diagramModelClass [
+	^ BormORModel
 ]
 
 { #category : 'running' }
-OPBormRelationshipControllerTest >> setUpSource [
-	sourceController := self sourceControllerClass new.
-	sourceController diagramController: diagramController.
-	sourceController createModelIn: diagramController model
+OPBormRelationshipControllerTest >> setUpSourceModel [
+
+	| participant |
+	participant := BormParticipant new.
+	diagramController model add: participant.
+
+	^ sourceModel := creationTargetController createModelIn: participant
 ]
 
-{ #category : 'as yet unclassified' }
-OPBormRelationshipControllerTest >> sourceControllerClass [
-	^ OPBormActivityController
+{ #category : 'running' }
+OPBormRelationshipControllerTest >> setUpTargetModel [
+
+	| participant |
+	participant := BormParticipant new.
+	diagramController model add: participant.
+
+	targetModel := targetController createModelIn: participant
 ]
diff --git a/repository/OpenPonk-BormEditor/OPBormStateControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormStateControllerTest.class.st
index 52d8e15..52118b8 100644
--- a/repository/OpenPonk-BormEditor/OPBormStateControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormStateControllerTest.class.st
@@ -3,7 +3,7 @@ A BormStateControllerTest is a test class for testing the behavior of BormStateC
 "
 Class {
 	#name : 'OPBormStateControllerTest',
-	#superclass : 'OPBormControllerTest',
+	#superclass : 'OPBormProcessNodeControllerTest',
 	#category : 'OpenPonk-BormEditor-Tests',
 	#package : 'OpenPonk-BormEditor',
 	#tag : 'Tests'
@@ -15,21 +15,21 @@ OPBormStateControllerTest >> controllerClass [
 ]
 
 { #category : 'accessing' }
-OPBormStateControllerTest >> diagramElementClass [
-	^ BormStateShape
+OPBormStateControllerTest >> creationTargetControllerClass [
+	^ OPBormParticipantController
 ]
 
 { #category : 'accessing' }
-OPBormStateControllerTest >> modelClass [
-	^ BormState
+OPBormStateControllerTest >> creationTargetModelClass [
+	^ BormParticipant
 ]
 
 { #category : 'accessing' }
-OPBormStateControllerTest >> targetControllerClass [
-	^ OPBormParticipantController
+OPBormStateControllerTest >> diagramElementClass [
+	^ BormStateShape
 ]
 
 { #category : 'accessing' }
-OPBormStateControllerTest >> targetModelClass [
-	^ BormParticipant
+OPBormStateControllerTest >> modelClass [
+	^ BormState
 ]
diff --git a/repository/OpenPonk-BormEditor/OPBormTransitionController.class.st b/repository/OpenPonk-BormEditor/OPBormTransitionController.class.st
index 68febef..a0926ee 100644
--- a/repository/OpenPonk-BormEditor/OPBormTransitionController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormTransitionController.class.st
@@ -17,16 +17,6 @@ OPBormTransitionController >> canBeTargetForDataFlow: aDataFlow [
 	^ false
 ]
 
-{ #category : 'hooks' }
-OPBormTransitionController >> createModelIn: aParentModel [
-	self model: self modelClass new.
-	model source: self source model.
-	model target: self target model.
-	source model addTransition: model.
-	target model addTransition: model.
-	^ model
-]
-
 { #category : 'construction' }
 OPBormTransitionController >> diagramElementClass [
 
@@ -38,6 +28,22 @@ OPBormTransitionController >> modelClass [
 	^ BormTransition
 ]
 
+{ #category : 'hooks' }
+OPBormTransitionController >> modelSource: aModel in: aParentModel [
+
+	(super modelSource: aModel in: aParentModel) ifFalse: [ ^ false ].
+	self modelSource addTransition: model.
+	^ true
+]
+
+{ #category : 'hooks' }
+OPBormTransitionController >> modelTarget: aModel in: aParentModel [
+
+	(super modelTarget: aModel in: aParentModel) ifFalse: [ ^ false ].
+	self modelTarget addTransition: model.
+	^ true
+]
+
 { #category : 'destruction' }
 OPBormTransitionController >> removeModel [
 	self model target removeTransition: self model.
diff --git a/repository/OpenPonk-BormEditor/OPBormTransitionControllerTest.class.st b/repository/OpenPonk-BormEditor/OPBormTransitionControllerTest.class.st
index 5799e44..18ddd07 100644
--- a/repository/OpenPonk-BormEditor/OPBormTransitionControllerTest.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormTransitionControllerTest.class.st
@@ -9,6 +9,20 @@ Class {
 	#tag : 'Tests'
 }
 
+{ #category : 'initialization' }
+OPBormTransitionControllerTest >> assignModelSource [
+
+	super assignModelSource.
+	model source addTransition: model
+]
+
+{ #category : 'initialization' }
+OPBormTransitionControllerTest >> assignModelTarget [
+
+	super assignModelTarget.
+	model target addTransition: model
+]
+
 { #category : 'accessing' }
 OPBormTransitionControllerTest >> controllerClass [
 	^ OPBormTransitionController
@@ -26,6 +40,21 @@ OPBormTransitionControllerTest >> modelClass [
 ]
 
 { #category : 'as yet unclassified' }
-OPBormTransitionControllerTest >> targetControllerClass [
+OPBormTransitionControllerTest >> sourceControllerClass [
 	^ OPBormStateController
 ]
+
+{ #category : 'as yet unclassified' }
+OPBormTransitionControllerTest >> sourceModelClass [
+	^ BormState
+]
+
+{ #category : 'as yet unclassified' }
+OPBormTransitionControllerTest >> targetControllerClass [
+	^ OPBormActivityController
+]
+
+{ #category : 'as yet unclassified' }
+OPBormTransitionControllerTest >> targetModelClass [
+	^ BormActivity
+]