diff --git a/dotnet/IEC61850forCSharp/IEC61850ClientAPI.cs b/dotnet/IEC61850forCSharp/IEC61850ClientAPI.cs
index b17317c4..236439fc 100644
--- a/dotnet/IEC61850forCSharp/IEC61850ClientAPI.cs
+++ b/dotnet/IEC61850forCSharp/IEC61850ClientAPI.cs
@@ -371,6 +371,20 @@ namespace IEC61850
 			static extern IntPtr IedConnection_queryLogByTime (IntPtr self, out int error, string logReference,
                   ulong startTime, ulong endTime, out bool moreFollows);
 
+
+			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
+			static extern IntPtr IedConnection_getRCBValues (IntPtr connection, out int error, string rcbReference, IntPtr updateRcb);
+
+			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
+			static extern void IedConnection_setRCBValues (IntPtr connection, out int error, IntPtr rcb, UInt32 parametersMask, bool singleRequest);
+
+			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
+			static extern void IedConnection_installReportHandler (IntPtr connection, string rcbReference, string rptId, InternalReportHandler handler,
+				IntPtr handlerParameter);
+
+			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
+			static extern void IedConnection_uninstallReportHandler(IntPtr connection, string rcbReference);
+
 
             /********************
             * FileDirectoryEntry
@@ -436,7 +450,6 @@ namespace IEC61850
 			public void Dispose()
 			{
 				if (connection != IntPtr.Zero) {
-					cleanupRCBs ();
 
 					IedConnection_destroy (connection);
 
@@ -446,11 +459,7 @@ namespace IEC61850
 
             ~IedConnection ()
             {
-				if (connection != IntPtr.Zero) {
-					cleanupRCBs ();
-
-					IedConnection_destroy (connection);
-				}
+				Dispose ();
             }
 
             private IsoConnectionParameters isoConnectionParameters = null;
@@ -1436,6 +1445,39 @@ namespace IEC61850
 
 				return newList;
 			}
+
+			internal void UninstallReportHandler (string objectReference)
+			{
+				if (connection != IntPtr.Zero) {
+					IedConnection_uninstallReportHandler (connection, objectReference);
+				}
+			}
+
+			internal void InstallReportHandler (string objectReference, string reportId, InternalReportHandler internalHandler)
+			{
+				if (connection != IntPtr.Zero) {
+					IedConnection_installReportHandler (connection, objectReference, reportId, internalHandler, IntPtr.Zero);
+				}
+			}
+
+			internal void GetRCBValues(out int error, string objectReference, IntPtr updateRcb)
+			{
+				if (connection != IntPtr.Zero) {
+					IedConnection_getRCBValues (connection, out error, objectReference, updateRcb);
+				} else {
+					error = 1; /* not connected */
+				}
+			}
+
+			internal void SetRCBValues(out int error, IntPtr rcb, UInt32 parametersMask, bool singleRequest)
+			{
+				if (connection != IntPtr.Zero) {
+					IedConnection_setRCBValues (connection, out error, rcb, parametersMask, singleRequest);
+				} else {
+					error = 1; /* not connected */
+				}
+			}
+
 		}
 
 		public class IedConnectionException : Exception
diff --git a/dotnet/IEC61850forCSharp/ReportControlBlock.cs b/dotnet/IEC61850forCSharp/ReportControlBlock.cs
index ad9f5da3..7d13a674 100644
--- a/dotnet/IEC61850forCSharp/ReportControlBlock.cs
+++ b/dotnet/IEC61850forCSharp/ReportControlBlock.cs
@@ -1,7 +1,7 @@
 /*
  *  ReportControlBlock.cs
  *
- *  Copyright 2014 Michael Zillgith
+ *  Copyright 2014-2018 Michael Zillgith
  *
  *  This file is part of libIEC61850.
  *
@@ -36,6 +36,9 @@ namespace IEC61850
         /// </summary>
 		public delegate void ReportHandler (Report report, object parameter);
 
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		internal delegate void InternalReportHandler (IntPtr parameter, IntPtr report);
+
         /// <summary>
         /// Report control block (RCB) representation.
         /// </summary>
@@ -44,16 +47,13 @@ namespace IEC61850
         /// Values from the server will only be read when the GetRCBValues method is called.
         /// Values at the server are only affected when the SetRCBValues method is called.
         /// </description>
-		public class ReportControlBlock
+		public class ReportControlBlock : IDisposable
 		{
 			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
 			static extern IntPtr ClientReportControlBlock_create (string dataAttributeReference);
 
 			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
-			static extern IntPtr IedConnection_getRCBValues (IntPtr connection, out int error, string rcbReference, IntPtr updateRcb);
-
-			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
-			static extern void IedConnection_setRCBValues (IntPtr connection, out int error, IntPtr rcb, UInt32 parametersMask, bool singleRequest);
+			static extern void ClientReportControlBlock_destroy (IntPtr self);
 
 			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
             [return: MarshalAs(UnmanagedType.I1)]
@@ -147,18 +147,7 @@ namespace IEC61850
 			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
 			static extern IntPtr ClientReportControlBlock_getOwner (IntPtr self);
 
-			[DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
-			static extern void IedConnection_installReportHandler (IntPtr connection, string rcbReference, string rptId, InternalReportHandler handler,
-        		IntPtr handlerParameter);
-
-            [DllImport("iec61850", CallingConvention = CallingConvention.Cdecl)]
-            static extern void IedConnection_uninstallReportHandler(IntPtr connection, string rcbReference);
-
-            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
-			private delegate void InternalReportHandler (IntPtr parameter, IntPtr report);
-
 			private IntPtr self;
-			private IntPtr connection;
 			private IedConnection iedConnection = null;
 			private string objectReference;
 			private bool flagRptId = false;
@@ -221,14 +210,11 @@ namespace IEC61850
 			internal ReportControlBlock (string objectReference, IedConnection iedConnection, IntPtr connection)
 			{
 				self = ClientReportControlBlock_create (objectReference);
-				this.iedConnection = iedConnection;
-				this.connection = connection;
-				this.objectReference = objectReference;
-			}
 
-			internal void DisposeInternal() 
-			{
-				IedConnection_uninstallReportHandler(connection, objectReference);
+				if (self != IntPtr.Zero) {
+					this.iedConnection = iedConnection;
+					this.objectReference = objectReference;
+				}
 			}
 
 			/// <summary>
@@ -239,11 +225,25 @@ namespace IEC61850
 			/// After calling <see cref="Dispose"/>, you must release all references to the
 			/// <see cref="IEC61850.Client.ReportControlBlock"/> so the garbage collector can reclaim the memory that the
 			/// <see cref="IEC61850.Client.ReportControlBlock"/> was occupying.</remarks>
-			public void Dispose() 
+			public void Dispose()
 			{
-				DisposeInternal ();
+				lock (this) {
+					if (self != IntPtr.Zero) {
+
+						iedConnection.UninstallReportHandler (objectReference);
+
+						iedConnection.RemoveRCB (this);
+
+						ClientReportControlBlock_destroy (self);
 
-				iedConnection.RemoveRCB (this);
+						self = IntPtr.Zero;
+					}
+				}
+			}
+
+			~ReportControlBlock() 
+			{
+				Dispose ();
 			}
 
 			public string GetObjectReference ()
@@ -279,9 +279,10 @@ namespace IEC61850
                     {
                         internalHandler =  new InternalReportHandler(internalReportHandler);
                     }
+						
+					iedConnection.InstallReportHandler (objectReference, reportId, internalHandler);
 
-                    IedConnection_installReportHandler(this.connection, objectReference, reportId, internalHandler, IntPtr.Zero);
-					reportHandlerInstalled = true;
+                	reportHandlerInstalled = true;
 				}
 			}
 
@@ -293,7 +294,7 @@ namespace IEC61850
 			{
 				int error;
 
-				IedConnection_getRCBValues (connection, out error, objectReference, self);
+				iedConnection.GetRCBValues (out error, objectReference, self);
 
 				if (error != 0)
 					throw new IedConnectionException ("getRCBValues service failed", error);
@@ -370,7 +371,7 @@ namespace IEC61850
 
                 int error;
 
-                IedConnection_setRCBValues (connection, out error, self, parametersMask, singleRequest);
+				iedConnection.SetRCBValues (out error, self, parametersMask, singleRequest);
 
 				resetSendFlags();
 
diff --git a/dotnet/IEC61850forCSharp/Reporting.cs b/dotnet/IEC61850forCSharp/Reporting.cs
index dfbf6d6b..90ddba2d 100644
--- a/dotnet/IEC61850forCSharp/Reporting.cs
+++ b/dotnet/IEC61850forCSharp/Reporting.cs
@@ -35,17 +35,6 @@ namespace IEC61850
 
 			private List<ReportControlBlock> activeRCBs = null;
 
-			private void cleanupRCBs() 
-			{
-				if (activeRCBs != null) {
-
-					foreach (ReportControlBlock rcb in activeRCBs) {
-						rcb.DisposeInternal ();
-					}
-				}
-
-			}
-
 			public ReportControlBlock GetReportControlBlock (string rcbObjectReference)
 			{
 				var newRCB = new ReportControlBlock (rcbObjectReference, this, connection);