Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMergeHandler.cs
===================================================================
diff -u -r4c958ce7ec9ae0247146de8bf83b5495a6ac2ec0 -r7c6b0a809f0c14f6192e9518a92192bf59aafd15
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMergeHandler.cs	(.../AssessmentSectionMergeHandler.cs)	(revision 4c958ce7ec9ae0247146de8bf83b5495a6ac2ec0)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMergeHandler.cs	(.../AssessmentSectionMergeHandler.cs)	(revision 7c6b0a809f0c14f6192e9518a92192bf59aafd15)
@@ -37,6 +37,7 @@
 using Ringtoets.GrassCoverErosionOutwards.Data;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.Integration.Data;
+using Ringtoets.Integration.Data.Merge;
 using Ringtoets.Integration.Data.StandAlone;
 using Ringtoets.Integration.Plugin.Properties;
 using Ringtoets.MacroStabilityInwards.Data;
@@ -105,6 +106,16 @@
             AfterMerge(changedObjects);
         }
 
+        public void PerformMerge(AssessmentSection targetAssessmentSection, AssessmentSectionMergeData mergeData)
+        {
+            if (mergeData == null)
+            {
+                throw new ArgumentNullException(nameof(mergeData));
+            }
+
+            PerformMerge(targetAssessmentSection, mergeData.AssessmentSection, mergeData.FailureMechanisms);
+        }
+
         private void BeforeMerge(AssessmentSection assessmentSection)
         {
             viewCommands.RemoveAllViewsForItem(assessmentSection);
Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/IAssessmentSectionMergeHandler.cs
===================================================================
diff -u -r1604f9968c87181d6e94d89b287fc8dd5a85854b -r7c6b0a809f0c14f6192e9518a92192bf59aafd15
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/IAssessmentSectionMergeHandler.cs	(.../IAssessmentSectionMergeHandler.cs)	(revision 1604f9968c87181d6e94d89b287fc8dd5a85854b)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/IAssessmentSectionMergeHandler.cs	(.../IAssessmentSectionMergeHandler.cs)	(revision 7c6b0a809f0c14f6192e9518a92192bf59aafd15)
@@ -23,6 +23,7 @@
 using System.Collections.Generic;
 using Ringtoets.Common.Data.FailureMechanism;
 using Ringtoets.Integration.Data;
+using Ringtoets.Integration.Data.Merge;
 
 namespace Ringtoets.Integration.Plugin.Merge
 {
@@ -40,5 +41,13 @@
         /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
         void PerformMerge(AssessmentSection targetAssessmentSection, AssessmentSection sourceAssessmentSection,
                           IEnumerable<IFailureMechanism> failureMechanismsToMerge);
+
+        /// <summary>
+        /// Performs the merge.
+        /// </summary>
+        /// <param name="targetAssessmentSection">The assessment section to merge to.</param>
+        /// <param name="mergeData">The data to merge.</param>
+        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
+        void PerformMerge(AssessmentSection targetAssessmentSection, AssessmentSectionMergeData mergeData);
     }
 }
\ No newline at end of file
Index: Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionMergeHandlerTest.cs
===================================================================
diff -u -r4c958ce7ec9ae0247146de8bf83b5495a6ac2ec0 -r7c6b0a809f0c14f6192e9518a92192bf59aafd15
--- Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionMergeHandlerTest.cs	(.../AssessmentSectionMergeHandlerTest.cs)	(revision 4c958ce7ec9ae0247146de8bf83b5495a6ac2ec0)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionMergeHandlerTest.cs	(.../AssessmentSectionMergeHandlerTest.cs)	(revision 7c6b0a809f0c14f6192e9518a92192bf59aafd15)
@@ -40,6 +40,7 @@
 using Ringtoets.GrassCoverErosionOutwards.Data.TestUtil;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.Integration.Data;
+using Ringtoets.Integration.Data.Merge;
 using Ringtoets.Integration.Plugin.Merge;
 using Ringtoets.MacroStabilityInwards.Data;
 using Ringtoets.Piping.Data;
@@ -141,6 +142,24 @@
         }
 
         [Test]
+        public void PerformMerge_MergeDataNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var viewCommands = mocks.StrictMock<IViewCommands>();
+            mocks.ReplayAll();
+
+            var handler = new AssessmentSectionMergeHandler(viewCommands);
+
+            // Call
+            TestDelegate call = () => handler.PerformMerge(new AssessmentSection(AssessmentSectionComposition.Dike), null);
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(call);
+            Assert.AreEqual("mergeData", exception.ParamName);
+        }
+
+        [Test]
         public void PerformMerge_WithAllData_AllViewsForTargetAssessmentSectionClosed()
         {
             // Setup