Index: Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/CombinationType.cs
===================================================================
diff -u
--- Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/CombinationType.cs	(revision 0)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/CombinationType.cs	(revision a82f053cd598d56bb1b7b8df663d104d7b9c1214)
@@ -0,0 +1,32 @@
+// 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.
+
+namespace Ringtoets.Common.Data.IllustrationPoints
+{
+    /// <summary>
+    /// The ways two illustration points can be combined in a single fault tree node.
+    /// </summary>
+    public enum CombinationType
+    {
+        Or,
+        And
+    }
+}
\ No newline at end of file
Index: Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/FaultTreeIllustrationPoint.cs
===================================================================
diff -u -r1f8455066f5be4241f587c34283f1d7f8a85f78e -ra82f053cd598d56bb1b7b8df663d104d7b9c1214
--- Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/FaultTreeIllustrationPoint.cs	(.../FaultTreeIllustrationPoint.cs)	(revision 1f8455066f5be4241f587c34283f1d7f8a85f78e)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/IllustrationPoints/FaultTreeIllustrationPoint.cs	(.../FaultTreeIllustrationPoint.cs)	(revision a82f053cd598d56bb1b7b8df663d104d7b9c1214)
@@ -21,7 +21,7 @@
 
 using System;
 using System.Collections.Generic;
-using Core.Common.Base.Data;
+using System.ComponentModel;
 
 namespace Ringtoets.Common.Data.IllustrationPoints
 {
@@ -30,29 +30,66 @@
     /// </summary>
     public class FaultTreeIllustrationPoint : IllustrationPointBase
     {
+        private CombinationType combinationType;
+
         /// <summary>
         /// Creates a new instance of <see cref="FaultTreeIllustrationPoint"/>.
         /// </summary>
         /// <param name="name">The name of the illustration point node.</param>
         /// <param name="beta">The beta value of this illustration point.</param>
         /// <param name="stochasts">A collection of <see cref="Stochasts"/>
         /// that are associated with this illustration point node.</param>
+        /// <param name="combinationType">The way to combine two nodes into a single
+        /// tree node element in the fault tree.</param>
         /// <exception cref="ArgumentNullException">Thrown when <paramref name="name"/> or 
         /// <paramref name="stochasts"/> is <c>null</c>.</exception>
-        public FaultTreeIllustrationPoint(string name, double beta, IEnumerable<Stochast> stochasts)
+        /// <exception cref="InvalidEnumArgumentException">Thrown when attempting 
+        /// to set invalid enum value of type <see cref="CombinationType"/>.</exception>
+        public FaultTreeIllustrationPoint(string name,
+                                          double beta,
+                                          IEnumerable<Stochast> stochasts,
+                                          CombinationType combinationType)
             : base(name, beta)
         {
             if (stochasts == null)
             {
                 throw new ArgumentNullException(nameof(stochasts));
             }
 
+            CombinationType = combinationType;
             Stochasts = stochasts;
         }
 
         /// <summary>
         /// Gets the stochasts that belong to this illustration point.
         /// </summary>
         public IEnumerable<Stochast> Stochasts { get; }
+
+        /// <summary>
+        /// Gets the combination type corresponding to this illustration point.
+        /// </summary>
+        /// <exception cref="InvalidEnumArgumentException">Thrown when attempting 
+        /// to set invalid enum value of type <see cref="CombinationType"/>.</exception>
+        public CombinationType CombinationType
+        {
+            get
+            {
+                return combinationType;
+            }
+            private set
+            {
+                switch (value)
+                {
+                    case CombinationType.And:
+                        combinationType = value;
+                        break;
+                    case CombinationType.Or:
+                        combinationType = value;
+                        break;
+                    default:
+                        throw new InvalidEnumArgumentException("value", (int) value, typeof(CombinationType));
+                }
+            }
+        }
     }
 }
\ No newline at end of file
Index: Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj
===================================================================
diff -u -r1f8455066f5be4241f587c34283f1d7f8a85f78e -ra82f053cd598d56bb1b7b8df663d104d7b9c1214
--- Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj	(.../Ringtoets.Common.Data.csproj)	(revision 1f8455066f5be4241f587c34283f1d7f8a85f78e)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj	(.../Ringtoets.Common.Data.csproj)	(revision a82f053cd598d56bb1b7b8df663d104d7b9c1214)
@@ -67,6 +67,7 @@
     <Compile Include="Hydraulics\HydraulicBoundaryLocationCalculation.cs" />
     <Compile Include="Hydraulics\HydraulicBoundaryLocationCalculationInput.cs" />
     <Compile Include="Hydraulics\HydraulicBoundaryLocationOutput.cs" />
+    <Compile Include="IllustrationPoints\CombinationType.cs" />
     <Compile Include="IllustrationPoints\FaultTreeIllustrationPoint.cs" />
     <Compile Include="IllustrationPoints\GeneralResultSubMechanismIllustrationPoint.cs" />
     <Compile Include="IllustrationPoints\GeneralResultSubMechanismIllustrationPointExtensions.cs" />
Index: Ringtoets/Common/test/Ringtoets.Common.Data.Test/IllustrationPoints/FaultTreeIllustrationPointTest.cs
===================================================================
diff -u -r1f8455066f5be4241f587c34283f1d7f8a85f78e -ra82f053cd598d56bb1b7b8df663d104d7b9c1214
--- Ringtoets/Common/test/Ringtoets.Common.Data.Test/IllustrationPoints/FaultTreeIllustrationPointTest.cs	(.../FaultTreeIllustrationPointTest.cs)	(revision 1f8455066f5be4241f587c34283f1d7f8a85f78e)
+++ Ringtoets/Common/test/Ringtoets.Common.Data.Test/IllustrationPoints/FaultTreeIllustrationPointTest.cs	(.../FaultTreeIllustrationPointTest.cs)	(revision a82f053cd598d56bb1b7b8df663d104d7b9c1214)
@@ -21,7 +21,9 @@
 
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Linq;
+using Core.Common.TestUtil;
 using NUnit.Framework;
 using Ringtoets.Common.Data.IllustrationPoints;
 using Ringtoets.Common.Data.TestUtil;
@@ -36,8 +38,10 @@
         {
             // Call
             TestDelegate call = () => new FaultTreeIllustrationPoint(null,
-                                                                     12.3, 
-                                                                     Enumerable.Empty<Stochast>());
+                                                                     12.3,
+                                                                     Enumerable.Empty<Stochast>(),
+                                                                     CombinationType.And);
+            ;
             // Assert
             var exception = Assert.Throws<ArgumentNullException>(call);
             Assert.AreEqual("name", exception.ParamName);
@@ -48,18 +52,39 @@
         {
             // Call
             TestDelegate call = () => new FaultTreeIllustrationPoint("Test",
-                                                                     12.3, 
-                                                                     null);
+                                                                     12.3,
+                                                                     null,
+                                                                     CombinationType.And);
 
             // Assert
             var exception = Assert.Throws<ArgumentNullException>(call);
             Assert.AreEqual("stochasts", exception.ParamName);
         }
 
         [Test]
-        public void Constructor_ValidArguments_ReturnsExpectedValues()
+        public void Constructor_InvalidCombinationType_ThrowsInvalidEnumArgumentException()
         {
             // Setup
+            var invalidEnum = (CombinationType) 9001;
+
+            // Call
+            TestDelegate call = () => new FaultTreeIllustrationPoint("Test", 12.3,
+                                                                     Enumerable.Empty<Stochast>(),
+                                                                     invalidEnum);
+
+            // Assert
+            const string expectedMessage = "The value of argument 'value' (9001) is invalid for Enum type 'CombinationType'.";
+            var exception = 
+                TestHelper.AssertThrowsArgumentExceptionAndTestMessage<InvalidEnumArgumentException>(call, expectedMessage);
+            Assert.AreEqual("value", exception.ParamName);
+        }
+
+        [Test]
+        [TestCase(CombinationType.And)]
+        [TestCase(CombinationType.Or)]
+        public void Constructor_ValidArguments_ReturnsExpectedValues(CombinationType combinationType)
+        {
+            // Setup
             const string name = "Fault tree illustration point name";
 
             var random = new Random(21);
@@ -68,14 +93,15 @@
             IEnumerable<Stochast> stochasts = Enumerable.Empty<Stochast>();
 
             // Call
-            var illustrationPoint = new FaultTreeIllustrationPoint(name, beta, stochasts);
+            var illustrationPoint = new FaultTreeIllustrationPoint(name, beta, stochasts, combinationType);
 
             // Assert
             Assert.IsInstanceOf<IllustrationPointBase>(illustrationPoint);
 
             Assert.AreEqual(name, illustrationPoint.Name);
             Assert.AreSame(stochasts, illustrationPoint.Stochasts);
             Assert.AreEqual(beta, illustrationPoint.Beta, illustrationPoint.Beta.GetAccuracy());
+            Assert.AreEqual(combinationType, illustrationPoint.CombinationType);
         }
     }
 }
\ No newline at end of file