Index: Ringtoets/Integration/src/Ringtoets.Integration.Forms/PropertyClasses/FailureMechanismContributionContextProperties.cs
===================================================================
diff -u -r1ddd0ecb63ccdcb00ce2f1f757ba5e0c64a5fb90 -rc8f94bae0d4f9b0c33bfd871991a969b203e3f45
--- Ringtoets/Integration/src/Ringtoets.Integration.Forms/PropertyClasses/FailureMechanismContributionContextProperties.cs	(.../FailureMechanismContributionContextProperties.cs)	(revision 1ddd0ecb63ccdcb00ce2f1f757ba5e0c64a5fb90)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Forms/PropertyClasses/FailureMechanismContributionContextProperties.cs	(.../FailureMechanismContributionContextProperties.cs)	(revision c8f94bae0d4f9b0c33bfd871991a969b203e3f45)
@@ -24,7 +24,6 @@
 using Core.Common.Base;
 using Core.Common.Gui.Attributes;
 using Core.Common.Gui.PropertyBag;
-using Core.Common.Utils;
 using Core.Common.Utils.Attributes;
 using Core.Common.Utils.Reflection;
 using Ringtoets.Common.Data.AssessmentSection;
@@ -46,15 +45,22 @@
         [ResourcesCategory(typeof(RingtoetsCommonFormsResources), "Categories_General")]
         [ResourcesDisplayName(typeof(Resources), "FailureMechanismContribution_Composition_DisplayName")]
         [ResourcesDescription(typeof(Resources), "FailureMechanismContribution_Composition_Description")]
-        public string AssessmentSectionComposition
+        public AssessmentSectionComposition AssessmentSectionComposition
         {
             get
             {
-                return new EnumDisplayWrapper<AssessmentSectionComposition>(AssessmentSection.Composition).DisplayName;
+                return AssessmentSection.Composition;
             }
             set
             {
-                
+                if (compositionChangeHandler.ConfirmCompositionChange())
+                {
+                    IEnumerable<IObservable> changedObjects = compositionChangeHandler.ChangeComposition(AssessmentSection, value);
+                    foreach (IObservable changedObject in changedObjects)
+                    {
+                        changedObject.NotifyObservers();
+                    }
+                }
             }
         }
 
@@ -69,6 +75,15 @@
             }
             set
             {
+                if (value != 0 && normChangeHandler.ConfirmNormChange())
+                {
+                    double newNormValue = 1.0/Convert.ToInt32(value);
+                    IEnumerable<IObservable> changedObjects = normChangeHandler.ChangeNorm(AssessmentSection, newNormValue);
+                    foreach (IObservable changedObject in changedObjects)
+                    {
+                        changedObject.NotifyObservers();
+                    }
+                }
             }
         }
 
@@ -85,7 +100,7 @@
         [DynamicVisible]
         public IFailureMechanismContributionNormChangeHandler NormChangeHandler
         {
-            get
+            private get
             {
                 return normChangeHandler;
             }
@@ -106,7 +121,7 @@
         [DynamicVisible]
         public IAssessmentSectionCompositionChangeHandler CompositionChangeHandler
         {
-            get
+            private get
             {
                 return compositionChangeHandler;
             }
@@ -140,4 +155,4 @@
             return true;
         }
     }
-}
+}
\ No newline at end of file
Index: Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/PropertyClasses/FailureMechanismContributionContextPropertiesTest.cs
===================================================================
diff -u -r1ddd0ecb63ccdcb00ce2f1f757ba5e0c64a5fb90 -rc8f94bae0d4f9b0c33bfd871991a969b203e3f45
--- Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/PropertyClasses/FailureMechanismContributionContextPropertiesTest.cs	(.../FailureMechanismContributionContextPropertiesTest.cs)	(revision 1ddd0ecb63ccdcb00ce2f1f757ba5e0c64a5fb90)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/PropertyClasses/FailureMechanismContributionContextPropertiesTest.cs	(.../FailureMechanismContributionContextPropertiesTest.cs)	(revision c8f94bae0d4f9b0c33bfd871991a969b203e3f45)
@@ -24,20 +24,31 @@
 using System.Linq;
 using Core.Common.Gui.PropertyBag;
 using Core.Common.TestUtil;
+using NUnit.Extensions.Forms;
 using NUnit.Framework;
 using Rhino.Mocks;
 using Ringtoets.Common.Data.AssessmentSection;
 using Ringtoets.Common.Data.Contribution;
 using Ringtoets.Common.Data.FailureMechanism;
+using Ringtoets.Integration.Data;
 using Ringtoets.Integration.Forms.PropertyClasses;
+using Ringtoets.Integration.Forms.Views;
+using Ringtoets.Integration.Plugin.Handlers;
 
 namespace Ringtoets.Integration.Forms.Test.PropertyClasses
 {
     [TestFixture]
-    public class FailureMechanismContributionContextPropertiesTest
+    public class FailureMechanismContributionContextPropertiesTest : NUnitFormTest
     {
-        private readonly MockRepository mocks = new MockRepository();
+        private MockRepository mocks;
 
+        [SetUp]
+        public override void Setup()
+        {
+            base.Setup();
+            mocks = new MockRepository();
+        }
+
         [Test]
         public void DefaultConstructor_ExpectedValues()
         {
@@ -82,19 +93,16 @@
         }
 
         [Test]
-        [TestCase(AssessmentSectionComposition.Dike, "Dijk")]
-        [TestCase(AssessmentSectionComposition.Dune, "Duin")]
-        [TestCase(AssessmentSectionComposition.DikeAndDune, "Dijk / Duin")]
-        public void GetProperties_WithData_ReturnExpectedValues(AssessmentSectionComposition composition, string expectedValue)
+        public void GetProperties_WithData_ReturnExpectedValues()
         {
             // Setup
+            var assessmentSectionComposition = AssessmentSectionComposition.DikeAndDune;
             var assessmentSection = mocks.Stub<IAssessmentSection>();
-            assessmentSection.Stub(section => section.Composition).Return(composition);
+            assessmentSection.Stub(section => section.Composition).Return(assessmentSectionComposition);
             mocks.ReplayAll();
 
-            var failureMechanisms = Enumerable.Empty<IFailureMechanism>();
-
             int returnPeriod = 30000;
+            var failureMechanisms = Enumerable.Empty<IFailureMechanism>();
             var contribution = new FailureMechanismContribution(failureMechanisms, 1.1, 1.0/returnPeriod);
 
             // Call
@@ -106,7 +114,7 @@
 
             // Assert
             Assert.AreEqual(returnPeriod, properties.ReturnPeriod);
-            Assert.AreEqual(expectedValue, properties.AssessmentSectionComposition);
+            Assert.AreEqual(assessmentSectionComposition, properties.AssessmentSectionComposition);
             mocks.VerifyAll();
         }
 
@@ -137,5 +145,102 @@
             string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
             Assert.AreEqual("value", paramName);
         }
+
+        [Test]
+        [TestCase(true)]
+        [TestCase(false)]
+        public void GivenReturnPeriod_WhenConfirmingChanges_ReturnPeriodSet(bool confirmChange)
+        {
+            // Given
+            AssessmentSection assessmentSection = new AssessmentSection(AssessmentSectionComposition.Dike);
+            FailureMechanismContribution failureMechanismContribution = assessmentSection.FailureMechanismContribution;
+            int originalReturnPeriod = Convert.ToInt32(1/failureMechanismContribution.Norm);
+
+            var normChangeHandler = new FailureMechanismContributionNormChangeHandler();
+
+            var compositionChangeHandler = mocks.Stub<IAssessmentSectionCompositionChangeHandler>();
+            compositionChangeHandler.Stub(h => h.ConfirmCompositionChange()).Return(false);
+            mocks.ReplayAll();
+
+            var properties = new FailureMechanismContributionContextProperties()
+            {
+                Data = failureMechanismContribution,
+                AssessmentSection = assessmentSection,
+                NormChangeHandler = normChangeHandler,
+                CompositionChangeHandler = compositionChangeHandler
+            };
+
+            DialogBoxHandler = (name, wnd) =>
+            {
+                var messageBox = new MessageBoxTester(wnd);
+
+                if (confirmChange)
+                {
+                    messageBox.ClickOk();
+                }
+                else
+                {
+                    messageBox.ClickCancel();
+                }
+            };
+
+            // When
+            const int newReturnPeriod = 200;
+            properties.ReturnPeriod = newReturnPeriod;
+
+            // Then
+            Assert.AreEqual(confirmChange ? newReturnPeriod : originalReturnPeriod, properties.ReturnPeriod);
+            Assert.AreEqual(confirmChange ? 1.0/newReturnPeriod : 1.0/originalReturnPeriod, failureMechanismContribution.Norm);
+            mocks.VerifyAll();
+        }
+
+        [Test]
+        [TestCase(true)]
+        [TestCase(false)]
+        public void GivenAssessmentSectionComposition_WhenConfirmingChanges_AssessmentSectionCompositionSet(bool confirmChange)
+        {
+            // Given
+            const AssessmentSectionComposition originalComposition = AssessmentSectionComposition.Dike;
+            AssessmentSection assessmentSection = new AssessmentSection(originalComposition);
+            FailureMechanismContribution failureMechanismContribution = assessmentSection.FailureMechanismContribution;
+
+            var compositionChangeHandler = new AssessmentSectionCompositionChangeHandler();
+
+            var normChangeHandler = mocks.Stub<IFailureMechanismContributionNormChangeHandler>();
+            normChangeHandler.Stub(h => h.ConfirmNormChange())
+                             .Return(false);
+            mocks.ReplayAll();
+
+            var properties = new FailureMechanismContributionContextProperties()
+            {
+                Data = failureMechanismContribution,
+                AssessmentSection = assessmentSection,
+                NormChangeHandler = normChangeHandler,
+                CompositionChangeHandler = compositionChangeHandler
+            };
+
+            DialogBoxHandler = (name, wnd) =>
+            {
+                var messageBox = new MessageBoxTester(wnd);
+
+                if (confirmChange)
+                {
+                    messageBox.ClickOk();
+                }
+                else
+                {
+                    messageBox.ClickCancel();
+                }
+            };
+
+            // When
+            const AssessmentSectionComposition newComposition = AssessmentSectionComposition.DikeAndDune;
+            properties.AssessmentSectionComposition = newComposition;
+
+            // Then
+            Assert.AreEqual(confirmChange ? newComposition : originalComposition, properties.AssessmentSectionComposition);
+            Assert.AreEqual(confirmChange ? newComposition : originalComposition, assessmentSection.Composition);
+            mocks.VerifyAll();
+        }
     }
 }
\ No newline at end of file