Index: Demo/Ringtoets/src/Demo.Ringtoets/Commands/AddNewDemoAssessmentSectionCommand.cs
===================================================================
diff -u -r3d92d0715a889b25fcf76e04d6536168d670328c -r7135385a10443af1369b1b9e814b8b762366f64b
--- Demo/Ringtoets/src/Demo.Ringtoets/Commands/AddNewDemoAssessmentSectionCommand.cs	(.../AddNewDemoAssessmentSectionCommand.cs)	(revision 3d92d0715a889b25fcf76e04d6536168d670328c)
+++ Demo/Ringtoets/src/Demo.Ringtoets/Commands/AddNewDemoAssessmentSectionCommand.cs	(.../AddNewDemoAssessmentSectionCommand.cs)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -140,19 +140,21 @@
 
                 for (var i = 0; i < failureMechanisms.Length; i++)
                 {
+                    IFailureMechanism failureMechanism = failureMechanisms[i];
+
                     if (i == 0)
                     {
-                        
-                        var importer = new FailureMechanismSectionsImporter(failureMechanisms[i],
+                        var importer = new FailureMechanismSectionsImporter(failureMechanism,
                                                                             demoAssessmentSection.ReferenceLine,
-                                                                            filePath);
+                                                                            filePath,
+                                                                            new FailureMechanismSectionReplaceStrategy(failureMechanism));
                         importer.Import();
                     }
                     else
                     {
                         // Copy same FailureMechanismSection instances to other failure mechanisms
                         FailureMechanismSection[] clonedSections = failureMechanisms[0].Sections.Select(DeepCloneSection).ToArray();
-                        failureMechanisms[i].SetSections(clonedSections, filePath);
+                        failureMechanism.SetSections(clonedSections, filePath);
                     }
                 }
             }
Index: Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionReplaceStrategy.cs
===================================================================
diff -u
--- Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionReplaceStrategy.cs	(revision 0)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionReplaceStrategy.cs	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -0,0 +1,68 @@
+// Copyright (C) Stichting Deltares 2017. All rights reserved.
+//
+// This file is part of Ringtoets.
+//
+// Ringtoets is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using Ringtoets.Common.Data.FailureMechanism;
+
+namespace Ringtoets.Common.IO.FileImporters
+{
+    /// <summary>
+    /// A replace strategy that can be used to replace failure mechanism sections with
+    /// imported failure mechanism sections.
+    /// </summary>
+    public class FailureMechanismSectionReplaceStrategy : IFailureMechanismSectionUpdateStrategy
+    {
+        private readonly IFailureMechanism failureMechanism;
+
+        /// <summary>
+        /// Creates a new instance of <see cref="FailureMechanismSectionReplaceStrategy"/>.
+        /// </summary>
+        /// <param name="failureMechanism">The <see cref="IFailureMechanism"/> to set the sections to.</param>
+        /// <exception cref="ArgumentNullException">Thrown when <paramref name="failureMechanism"/>
+        /// is <c>null</c>.</exception>
+        public FailureMechanismSectionReplaceStrategy(IFailureMechanism failureMechanism)
+        {
+            if (failureMechanism == null)
+            {
+                throw new ArgumentNullException(nameof(failureMechanism));
+            }
+
+            this.failureMechanism = failureMechanism;
+        }
+
+        public void UpdateSectionsWithImportedData(IEnumerable<FailureMechanismSection> importedFailureMechanismSections,
+                                                   string sourcePath)
+        {
+            if (importedFailureMechanismSections == null)
+            {
+                throw new ArgumentNullException(nameof(importedFailureMechanismSections));
+            }
+
+            if (sourcePath == null)
+            {
+                throw new ArgumentNullException(nameof(sourcePath));
+            }
+
+            failureMechanism.SetSections(importedFailureMechanismSections, sourcePath);
+        }
+    }
+}
\ No newline at end of file
Index: Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionsImporter.cs
===================================================================
diff -u -r88ba44b92caad86cf1343d9c191bc22761463c8c -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionsImporter.cs	(.../FailureMechanismSectionsImporter.cs)	(revision 88ba44b92caad86cf1343d9c191bc22761463c8c)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/FailureMechanismSectionsImporter.cs	(.../FailureMechanismSectionsImporter.cs)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -48,23 +48,35 @@
         private const double lengthDifferenceTolerance = 1;
 
         private readonly ReferenceLine referenceLine;
+        private readonly IFailureMechanismSectionUpdateStrategy failureMechanismSectionUpdateStrategy;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="FailureMechanismSectionsImporter"/> class.
         /// </summary>
         /// <param name="importTarget">The failure mechanism to update.</param>
         /// <param name="referenceLine">The reference line used to check correspondence with.</param>
         /// <param name="filePath">The path to the file to import from.</param>
+        /// <param name="failureMechanismSectionUpdateStrategy">The strategy to update the failure mechanism sections
+        /// with the imported data.</param>
         /// <exception cref="ArgumentNullException">Thrown when any input argument is <c>null</c>.
         /// </exception>
-        public FailureMechanismSectionsImporter(IFailureMechanism importTarget, ReferenceLine referenceLine, string filePath) : base(filePath, importTarget)
+        public FailureMechanismSectionsImporter(IFailureMechanism importTarget,
+                                                ReferenceLine referenceLine,
+                                                string filePath,
+                                                IFailureMechanismSectionUpdateStrategy failureMechanismSectionUpdateStrategy) : base(filePath, importTarget)
         {
             if (referenceLine == null)
             {
                 throw new ArgumentNullException(nameof(referenceLine));
             }
 
+            if (failureMechanismSectionUpdateStrategy == null)
+            {
+                throw new ArgumentNullException(nameof(failureMechanismSectionUpdateStrategy));
+            }
+
             this.referenceLine = referenceLine;
+            this.failureMechanismSectionUpdateStrategy = failureMechanismSectionUpdateStrategy;
         }
 
         protected override bool OnImport()
@@ -227,7 +239,7 @@
         {
             IEnumerable<FailureMechanismSection> snappedSections = SnapReadSectionsToReferenceLine(failureMechanismSections, referenceLine);
 
-            ImportTarget.SetSections(snappedSections, FilePath);
+            failureMechanismSectionUpdateStrategy.UpdateSectionsWithImportedData(snappedSections, FilePath);
         }
 
         private static IEnumerable<FailureMechanismSection> SnapReadSectionsToReferenceLine(IEnumerable<FailureMechanismSection> failureMechanismSections,
Index: Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/IFailureMechanismSectionUpdateStrategy.cs
===================================================================
diff -u
--- Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/IFailureMechanismSectionUpdateStrategy.cs	(revision 0)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/FileImporters/IFailureMechanismSectionUpdateStrategy.cs	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -0,0 +1,45 @@
+// Copyright (C) Stichting Deltares 2017. All rights reserved.
+//
+// This file is part of Ringtoets.
+//
+// Ringtoets is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Ringtoets.Common.Data.Exceptions;
+using Ringtoets.Common.Data.FailureMechanism;
+
+namespace Ringtoets.Common.IO.FileImporters
+{
+    /// <summary>
+    /// Interface describing the method of updating the data model after new 
+    /// failure mechanism sections have been imported.
+    /// </summary>
+    public interface IFailureMechanismSectionUpdateStrategy
+    {
+        /// <summary>
+        /// Updates the data model with data from <paramref name="importedFailureMechanismSections"/>.
+        /// </summary>
+        /// <param name="importedFailureMechanismSections">The imported failure mechanism sections.</param>
+        /// <param name="sourcePath">The source path from where the failure mechanism sections were imported.</param>
+        /// <exception cref="ArgumentNullException">Thrown when any input argument is <c>null</c>.</exception>
+        void UpdateSectionsWithImportedData(IEnumerable<FailureMechanismSection> importedFailureMechanismSections,
+                                            string sourcePath);
+    }
+}
\ No newline at end of file
Index: Ringtoets/Common/src/Ringtoets.Common.IO/Ringtoets.Common.IO.csproj
===================================================================
diff -u -reb0206bf27d75fbfeb403b365a4218a228f007e4 -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Common/src/Ringtoets.Common.IO/Ringtoets.Common.IO.csproj	(.../Ringtoets.Common.IO.csproj)	(revision eb0206bf27d75fbfeb403b365a4218a228f007e4)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/Ringtoets.Common.IO.csproj	(.../Ringtoets.Common.IO.csproj)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -47,10 +47,13 @@
     <Compile Include="Configurations\Import\CalculationConfigurationImporter.cs" />
     <Compile Include="Exceptions\DistributionValidationException.cs" />
     <Compile Include="FileImporters\DikeProfilesImporter.cs" />
+    <Compile Include="FileImporters\FailureMechanismSectionReplaceStrategy.cs" />
     <Compile Include="FileImporters\FailureMechanismSectionsImporter.cs" />
+    <Compile Include="FileImporters\FailureMechanismSectionUpdateStrategy.cs" />
     <Compile Include="FileImporters\ForeshoreProfilesImporter.cs" />
     <Compile Include="FileImporters\HydraulicBoundaryDatabaseImporter.cs" />
     <Compile Include="FileImporters\IDikeProfileUpdateDataStrategy.cs" />
+    <Compile Include="FileImporters\IFailureMechanismSectionUpdateStrategy.cs" />
     <Compile Include="FileImporters\IForeshoreProfileUpdateDataStrategy.cs" />
     <Compile Include="FileImporters\MessageProviders\IImporterMessageProvider.cs" />
     <Compile Include="FileImporters\MessageProviders\ImportMessageProvider.cs" />
Index: Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionReplaceStrategyTest.cs
===================================================================
diff -u
--- Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionReplaceStrategyTest.cs	(revision 0)
+++ Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionReplaceStrategyTest.cs	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -0,0 +1,98 @@
+// Copyright (C) Stichting Deltares 2017. All rights reserved.
+//
+// This file is part of Ringtoets.
+//
+// Ringtoets is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System;
+using System.Linq;
+using NUnit.Framework;
+using Rhino.Mocks;
+using Ringtoets.Common.Data.FailureMechanism;
+using Ringtoets.Common.IO.FileImporters;
+
+namespace Ringtoets.Common.IO.Test.FileImporters
+{
+    [TestFixture]
+    public class FailureMechanismSectionReplaceStrategyTest
+    {
+        [Test]
+        public void Constructor_FailureMechanismNull_ThrowsArgumentNullException()
+        {
+            // Call
+            TestDelegate call = () => new FailureMechanismSectionReplaceStrategy(null);
+
+            // Assert
+            string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
+            Assert.AreEqual("failureMechanism", paramName);
+        }
+
+        [Test]
+        public void Constructor_ExpectedValues()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var failureMechanism = mocks.Stub<IFailureMechanism>();
+            mocks.ReplayAll();
+
+            // Call
+            var importer = new FailureMechanismSectionReplaceStrategy(failureMechanism);
+
+            // Assert
+            Assert.IsInstanceOf<IFailureMechanismSectionUpdateStrategy>(importer);
+            mocks.VerifyAll();
+        }
+
+        [Test]
+        public void UpdateSectionsWithImportedData_ImportedFailureMechanismSectionsNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var failureMechanism = mocks.Stub<IFailureMechanism>();
+            mocks.ReplayAll();
+
+            // Call
+            TestDelegate call = () => new FailureMechanismSectionReplaceStrategy(failureMechanism).UpdateSectionsWithImportedData(null, "");
+
+            // Assert
+            string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
+            Assert.AreEqual("importedFailureMechanismSections", paramName);
+            mocks.VerifyAll();
+        }
+
+        [Test]
+        public void UpdateSectionsWithImportedData_SourcePathNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var failureMechanism = mocks.Stub<IFailureMechanism>();
+            mocks.ReplayAll();
+
+            var failureMechanismSectionReplaceStrategy = new FailureMechanismSectionReplaceStrategy(failureMechanism);
+
+            // Call
+            TestDelegate call = () => failureMechanismSectionReplaceStrategy.UpdateSectionsWithImportedData(
+                Enumerable.Empty<FailureMechanismSection>(), null);
+
+            // Assert
+            string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
+            Assert.AreEqual("sourcePath", paramName);
+            mocks.VerifyAll();
+        }
+    }
+}
\ No newline at end of file
Index: Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionsImporterTest.cs
===================================================================
diff -u -r67846d2c26e292748851a4ecbee2a050ffffa721 -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionsImporterTest.cs	(.../FailureMechanismSectionsImporterTest.cs)	(revision 67846d2c26e292748851a4ecbee2a050ffffa721)
+++ Ringtoets/Common/test/Ringtoets.Common.IO.Test/FileImporters/FailureMechanismSectionsImporterTest.cs	(.../FailureMechanismSectionsImporterTest.cs)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -42,33 +42,36 @@
     public class FailureMechanismSectionsImporterTest
     {
         [Test]
-        public void Constructor_FailureMechanismNull_ThrowArgumentNullException()
+        public void Constructor_ReferenceLineNull_ThrowsArgumentNullException()
         {
             // Setup
-            var referenceLine = new ReferenceLine();
+            var mocks = new MockRepository();
+            var failureMechanism = mocks.Stub<IFailureMechanism>();
+            mocks.ReplayAll();
 
             // Call
-            TestDelegate call = () => new FailureMechanismSectionsImporter(null, referenceLine, "");
+            TestDelegate call = () => new FailureMechanismSectionsImporter(failureMechanism, null, "", new TestFailureMechanismSectionUpdateStrategy());
 
             // Assert
             string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
-            Assert.AreEqual("importTarget", paramName);
+            Assert.AreEqual("referenceLine", paramName);
+            mocks.VerifyAll();
         }
 
         [Test]
-        public void Constructor_ReferenceLineNull_ThrowsArgumentNullException()
+        public void Constructor_FailureMechanismSectionUpdateStrategyNull_ThrowsArgumentNullException()
         {
             // Setup
             var mocks = new MockRepository();
             var failureMechanism = mocks.Stub<IFailureMechanism>();
             mocks.ReplayAll();
 
             // Call
-            TestDelegate call = () => new FailureMechanismSectionsImporter(failureMechanism, null, "");
+            TestDelegate call = () => new FailureMechanismSectionsImporter(failureMechanism, new ReferenceLine(), "", null);
 
             // Assert
             string paramName = Assert.Throws<ArgumentNullException>(call).ParamName;
-            Assert.AreEqual("referenceLine", paramName);
+            Assert.AreEqual("failureMechanismSectionUpdateStrategy", paramName);
             mocks.VerifyAll();
         }
 
@@ -83,7 +86,7 @@
             var referenceLine = new ReferenceLine();
 
             // Call
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, referenceLine, "");
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, referenceLine, "", new TestFailureMechanismSectionUpdateStrategy());
 
             // Assert
             Assert.IsInstanceOf<FileImporterBase<IFailureMechanism>>(importer);
@@ -103,17 +106,19 @@
 
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
             var failureMechanism = new TestFailureMechanism();
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
+
             // Call
             bool importSuccessful = importer.Import();
 
             // Assert
             Assert.IsTrue(importSuccessful);
 
-            Assert.AreEqual(sectionsFilePath, failureMechanism.FailureMechanismSectionSourcePath);
-            FailureMechanismSection[] sections = failureMechanism.Sections.ToArray();
-            Assert.AreEqual(sectionCount, sections.Length);
+            Assert.AreEqual(sectionsFilePath, updateStrategy.SourcePath);
+            IEnumerable<FailureMechanismSection> sections = updateStrategy.ImportedFailureMechanismSections;
+            Assert.AreEqual(sectionCount, sections.Count());
             AssertSectionsAreValidForReferenceLine(sections, importReferenceLine);
         }
 
@@ -133,16 +138,18 @@
             {
                 new FailureMechanismSection("A", importReferenceLine.Points)
             });
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
+
             // Call
             bool importSuccessful = importer.Import();
 
             // Assert
             Assert.IsTrue(importSuccessful);
 
-            FailureMechanismSection[] sections = failureMechanism.Sections.ToArray();
-            Assert.AreEqual(62, sections.Length);
+            IEnumerable<FailureMechanismSection> sections = updateStrategy.ImportedFailureMechanismSections;
+            Assert.AreEqual(62, sections.Count());
             AssertSectionsAreValidForReferenceLine(sections, importReferenceLine);
         }
 
@@ -158,17 +165,18 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             bool importSuccessful = importer.Import();
 
             // Assert
             Assert.IsTrue(importSuccessful);
 
-            FailureMechanismSection[] sections = failureMechanism.Sections.ToArray();
-            Assert.AreEqual(7, sections.Length);
+            IEnumerable<FailureMechanismSection> sections = updateStrategy.ImportedFailureMechanismSections;
+            Assert.AreEqual(7, sections.Count());
             AssertSectionsAreValidForReferenceLine(sections, importReferenceLine);
         }
 
@@ -189,17 +197,18 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             bool importSuccessful = importer.Import();
 
             // Assert
             Assert.IsTrue(importSuccessful);
 
-            FailureMechanismSection[] sections = failureMechanism.Sections.ToArray();
-            Assert.AreEqual(7, sections.Length);
+            IEnumerable<FailureMechanismSection> sections = updateStrategy.ImportedFailureMechanismSections;
+            Assert.AreEqual(7, sections.Count());
             AssertSectionsAreValidForReferenceLine(sections, importReferenceLine);
         }
 
@@ -217,8 +226,9 @@
             var progressChangeNotifications = new List<ProgressNotification>();
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
             importer.SetProgressChanged((description, step, steps) => progressChangeNotifications.Add(new ProgressNotification(description, step, steps)));
 
             // Call
@@ -248,8 +258,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -274,8 +285,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -302,8 +314,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -332,8 +345,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -362,8 +376,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -389,8 +404,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -416,8 +432,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -444,8 +461,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -467,8 +485,9 @@
                                                                  Path.Combine("FailureMechanismSections", "vakindeling_Empty_Name_Value.shp"));
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, new ReferenceLine(), sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, new ReferenceLine(), sectionsFilePath, updateStrategy);
 
             // Call
             var importSuccessful = true;
@@ -494,8 +513,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
             importer.SetProgressChanged((description, step, steps) =>
             {
                 if (description.Contains("Inlezen vakindeling."))
@@ -527,8 +547,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
             importer.SetProgressChanged((description, step, steps) =>
             {
                 if (description.Contains("Valideren ingelezen vakindeling."))
@@ -560,8 +581,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
             importer.SetProgressChanged((description, step, steps) =>
             {
                 if (description.Contains("Geïmporteerde data toevoegen aan het toetsspoor."))
@@ -578,7 +600,7 @@
             // Assert
             TestHelper.AssertLogMessageIsGenerated(call, "Huidige actie was niet meer te annuleren en is daarom voortgezet.", 1);
             Assert.IsTrue(importSuccessful);
-            CollectionAssert.IsNotEmpty(failureMechanism.Sections);
+            CollectionAssert.IsNotEmpty(updateStrategy.ImportedFailureMechanismSections);
         }
 
         [Test]
@@ -593,8 +615,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
             importer.SetProgressChanged((description, step, steps) => importer.Cancel());
 
             Assert.IsFalse(importer.Import());
@@ -606,8 +629,8 @@
             // Assert
             Assert.IsTrue(importSuccessful);
 
-            FailureMechanismSection[] sections = failureMechanism.Sections.ToArray();
-            Assert.AreEqual(62, sections.Length);
+            IEnumerable<FailureMechanismSection> sections = updateStrategy.ImportedFailureMechanismSections;
+            Assert.AreEqual(62, sections.Count());
             AssertSectionsAreValidForReferenceLine(sections, importReferenceLine);
         }
 
@@ -628,8 +651,9 @@
             ReferenceLine importReferenceLine = ImportReferenceLine(referenceLineFilePath);
 
             var failureMechanism = new TestFailureMechanism();
+            var updateStrategy = new TestFailureMechanismSectionUpdateStrategy();
 
-            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath);
+            var importer = new FailureMechanismSectionsImporter(failureMechanism, importReferenceLine, sectionsFilePath, updateStrategy);
 
             importer.Import();
             failureMechanism.SectionResults.Attach(observable);
@@ -641,6 +665,22 @@
             mocks.VerifyAll();
         }
 
+        private class TestFailureMechanismSectionUpdateStrategy : IFailureMechanismSectionUpdateStrategy
+        {
+            public bool Updated { get; private set; }
+
+            public string SourcePath { get; private set; }
+
+            public IEnumerable<FailureMechanismSection> ImportedFailureMechanismSections { get; private set; }
+
+            public void UpdateSectionsWithImportedData(IEnumerable<FailureMechanismSection> importedFailureMechanismSections, string sourcePath)
+            {
+                Updated = true;
+                SourcePath = sourcePath;
+                ImportedFailureMechanismSections = importedFailureMechanismSections;
+            }
+        }
+
         private static ReferenceLine ImportReferenceLine(string referenceLineFilePath)
         {
             ReferenceLine importedReferenceLine = null;
@@ -663,12 +703,12 @@
             return importedReferenceLine;
         }
 
-        private void AssertSectionsAreValidForReferenceLine(FailureMechanismSection[] sections, ReferenceLine referenceLine)
+        private void AssertSectionsAreValidForReferenceLine(IEnumerable<FailureMechanismSection> sections, ReferenceLine referenceLine)
         {
             Point2D[] referenceLineGeometry = referenceLine.Points.ToArray();
 
             // 1. Start & End coherence:
-            Assert.AreEqual(referenceLineGeometry[0], sections[0].StartPoint,
+            Assert.AreEqual(referenceLineGeometry[0], sections.First().StartPoint,
                             "Start of the sections should correspond to the Start of the reference line.");
             Assert.AreEqual(referenceLineGeometry.Last(), sections.Last().EndPoint,
                             "End of the sections should correspond to the End of the reference line.");
Index: Ringtoets/Common/test/Ringtoets.Common.IO.Test/Ringtoets.Common.IO.Test.csproj
===================================================================
diff -u -reb0206bf27d75fbfeb403b365a4218a228f007e4 -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Common/test/Ringtoets.Common.IO.Test/Ringtoets.Common.IO.Test.csproj	(.../Ringtoets.Common.IO.Test.csproj)	(revision eb0206bf27d75fbfeb403b365a4218a228f007e4)
+++ Ringtoets/Common/test/Ringtoets.Common.IO.Test/Ringtoets.Common.IO.Test.csproj	(.../Ringtoets.Common.IO.Test.csproj)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -52,6 +52,7 @@
     <Compile Include="Configurations\Import\CalculationConfigurationImporterTest.cs" />
     <Compile Include="Exceptions\DistributionValidationExceptionTest.cs" />
     <Compile Include="FileImporters\DikeProfilesImporterTest.cs" />
+    <Compile Include="FileImporters\FailureMechanismSectionReplaceStrategyTest.cs" />
     <Compile Include="FileImporters\FailureMechanismSectionsImporterTest.cs" />
     <Compile Include="FileImporters\ForeshoreProfilesImporterTest.cs" />
     <Compile Include="FileImporters\HydraulicBoundaryDatabaseImporterTest.cs" />
Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/RingtoetsPlugin.cs
===================================================================
diff -u -r77f43b2f296c4b9515556f289d8b74bbb172f9cd -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/RingtoetsPlugin.cs	(.../RingtoetsPlugin.cs)	(revision 77f43b2f296c4b9515556f289d8b74bbb172f9cd)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/RingtoetsPlugin.cs	(.../RingtoetsPlugin.cs)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -649,7 +649,8 @@
                 IsEnabled = context => context.AssessmentSection.ReferenceLine != null,
                 CreateFileImporter = (context, filePath) => new FailureMechanismSectionsImporter(context.WrappedData,
                                                                                                  context.AssessmentSection.ReferenceLine,
-                                                                                                 filePath)
+                                                                                                 filePath,
+                                                                                                 new FailureMechanismSectionReplaceStrategy(context.WrappedData))
             };
             yield return new ImportInfo<ForeshoreProfilesContext>
             {
@@ -1332,6 +1333,7 @@
                       .AddOpenItem()
                       .AddSeparator()
                       .AddImportItem()
+                      .AddUpdateItem()
                       .AddSeparator()
                       .AddPropertiesItem()
                       .Build();
Index: Ringtoets/Integration/test/Ringtoets.Integration.TestUtil/DataImportHelper.cs
===================================================================
diff -u -ra90ecfec7dc128234360d4a55ee646928c133b75 -r7135385a10443af1369b1b9e814b8b762366f64b
--- Ringtoets/Integration/test/Ringtoets.Integration.TestUtil/DataImportHelper.cs	(.../DataImportHelper.cs)	(revision a90ecfec7dc128234360d4a55ee646928c133b75)
+++ Ringtoets/Integration/test/Ringtoets.Integration.TestUtil/DataImportHelper.cs	(.../DataImportHelper.cs)	(revision 7135385a10443af1369b1b9e814b8b762366f64b)
@@ -103,7 +103,10 @@
                                                                                    "traject_6-3_vakken.shx"))
             {
                 string filePath = Path.Combine(embeddedResourceFileWriter.TargetFolderPath, "traject_6-3_vakken.shp");
-                var activity = new FileImportActivity(new FailureMechanismSectionsImporter(failureMechanism, assessmentSection.ReferenceLine, filePath),
+                var activity = new FileImportActivity(new FailureMechanismSectionsImporter(failureMechanism, 
+                                                                                           assessmentSection.ReferenceLine, 
+                                                                                           filePath, 
+                                                                                           new FailureMechanismSectionReplaceStrategy(failureMechanism)),
                                                       "FailureMechanismSectionsImporter");
                 activity.Run();
                 activity.Finish();
@@ -132,19 +135,21 @@
                 IFailureMechanism[] failureMechanisms = targetFailureMechanisms.ToArray();
                 for (var i = 0; i < failureMechanisms.Length; i++)
                 {
+                    IFailureMechanism failureMechanism = failureMechanisms[i];
                     if (i == 0)
                     {
                         string filePath = Path.Combine(embeddedResourceFileWriter.TargetFolderPath,
                                                        "traject_6-3_vakken.shp");
-                        var importer = new FailureMechanismSectionsImporter(failureMechanisms[i],
+                        var importer = new FailureMechanismSectionsImporter(failureMechanism,
                                                                             assessmentSection.ReferenceLine,
-                                                                            filePath);
+                                                                            filePath,
+                                                                            new FailureMechanismSectionReplaceStrategy(failureMechanism));
                         importer.Import();
                     }
                     else
                     {
                         // Copy same FailureMechanismSection instances to other failure mechanisms
-                        FailureMechanismTestHelper.SetSections(failureMechanisms[i], failureMechanisms[0].Sections.Select(DeepCloneSection).ToList());
+                        FailureMechanismTestHelper.SetSections(failureMechanism, failureMechanisms[0].Sections.Select(DeepCloneSection).ToList());
                     }
                 }
             }