diff --git a/Triangle.NET/Triangle/Data/Triangle.cs b/Triangle.NET/Triangle/Data/Triangle.cs
index fef0b8e..adabc22 100644
--- a/Triangle.NET/Triangle/Data/Triangle.cs
+++ b/Triangle.NET/Triangle/Data/Triangle.cs
@@ -146,12 +146,22 @@ namespace TriangleNet.Data
         /// Gets a triangles' neighbor.
         /// </summary>
         /// <param name="index">The neighbor index (0, 1 or 2).</param>
-        /// <returns>The triangles' neigbbor.</returns>
+        /// <returns>The neigbbor opposite of vertex with given index.</returns>
         public ITriangle GetNeighbor(int index)
         {
             return neighbors[index].triangle == Mesh.dummytri ? null : neighbors[index].triangle;
         }
 
+        /// <summary>
+        /// Gets a triangles segment.
+        /// </summary>
+        /// <param name="index">The vertex index (0, 1 or 2).</param>
+        /// <returns>The segment opposite of vertex with given index.</returns>
+        public Segment GetSegment(int index)
+        {
+            return subsegs[index].seg == Mesh.dummysub ? null : subsegs[index].seg;
+        }
+
         /// <summary>
         /// Gets the triangle area constraint.
         /// </summary>
diff --git a/Triangle.NET/Triangle/Geometry/ITriangle.cs b/Triangle.NET/Triangle/Geometry/ITriangle.cs
index 78e8fae..8aa5dd1 100644
--- a/Triangle.NET/Triangle/Geometry/ITriangle.cs
+++ b/Triangle.NET/Triangle/Geometry/ITriangle.cs
@@ -63,10 +63,17 @@ namespace TriangleNet.Geometry
         /// <summary>
         /// Gets a triangles neighbor.
         /// </summary>
-        /// <param name="index">The neighbor index (0, 1 or 2).</param>
-        /// <returns>The triangles' neigbbor.</returns>
+        /// <param name="index">The vertex index (0, 1 or 2).</param>
+        /// <returns>The neigbbor opposite of vertex with given index.</returns>
         ITriangle GetNeighbor(int index);
 
+        /// <summary>
+        /// Gets a triangles segment.
+        /// </summary>
+        /// <param name="index">The vertex index (0, 1 or 2).</param>
+        /// <returns>The segment opposite of vertex with given index.</returns>
+        Segment GetSegment(int index);
+
         /// <summary>
         /// Triangle area constraint.
         /// </summary>
diff --git a/Triangle.NET/Triangle/IO/InputTriangle.cs b/Triangle.NET/Triangle/IO/InputTriangle.cs
index 917e889..61c0939 100644
--- a/Triangle.NET/Triangle/IO/InputTriangle.cs
+++ b/Triangle.NET/Triangle/IO/InputTriangle.cs
@@ -92,6 +92,11 @@ namespace TriangleNet.IO
             return null;
         }
 
+        public Segment GetSegment(int index)
+        {
+            return null;
+        }
+
         /// <summary>
         /// Gets the triangle area constraint.
         /// </summary>