diff --git a/Editor/ClusterEditor.cs b/Editor/ClusterEditor.cs
index c19cc2c..fe182c8 100644
--- a/Editor/ClusterEditor.cs
+++ b/Editor/ClusterEditor.cs
@@ -303,6 +303,11 @@ namespace NanoBrain.Unity {
                             synapse.weight = newWeight;
                             anythingChanged = true;
                         }
+                        bool isTrainable = EditorGUILayout.Toggle("Trainable", synapse.trainable);
+                        if (isTrainable != synapse.trainable) {
+                            synapse.trainable = isTrainable;
+                            anythingChanged = true;
+                        }
                         EditorGUI.indentLevel--;
                     }
                 }
diff --git a/Runtime/Scripts/Core/Synapse.cs b/Runtime/Scripts/Core/Synapse.cs
index a28626c..a0bf74d 100644
--- a/Runtime/Scripts/Core/Synapse.cs
+++ b/Runtime/Scripts/Core/Synapse.cs
@@ -19,6 +19,8 @@ namespace NanoBrain {
         /// </summary>
         public float weight;
 
+        public bool trainable = false;
+        
         /// <summary>
         /// Create a new Synapse
         /// </summary>