This is python 2.3. I start a toy .NET service. This is a C-sharp executable. In the C-sharp files, this code exists: namespace foo { public class Toy : MarshalByRefObject, IToy ... } In python, after loading an assembly, I can successfully do either: from CLR.foo import Toy from CLR.foo import IToy I can get a string for the url of the service from the config file. I then try: # using Toy also gives the same result remoteObj = System.Activator.GetObject(IToy, url) and it returns this for remoteObj: <CLR.System.MarshalByRefObject object at 0x0090D090> If I try to invoke a method on remoteObj, I get this error: AttributeError: 'MarshalByRefObject' object has no attribute 'methodName'. It is almost as if the remoteObj has not been cast to the correct type (Itoy). But if I do remoteObj.ToString() it returns 'foo.Toy'. If I just try to instantiate a local instance of Toy -- t = Toy() -- this succeeds, and I can successfully invoke the method that fails on the remoteObj. Any ideas why the remoteObj is failing? Thanks, Rick