:-O Didn't realise I was 'in the know'! You can just use the dispids from the IDL, preferably, as you said before, defined as constants somewhere. Flash will be using the predefined IDs, so it will be safe, and it's much less painful than implementing GetIDsOfNames, which you won't need. Don't know about the final note, I only use C++/C/C# with VBS thrown in. For what it's worth I usually 'handcode' the event sink so that the invoke function calls a pure virtual in a base class, then my concrete class provides the pure virtuals. This is occasionally useful if I need the same kind of sink somewhere else in the project or another app. Steve S

If all you need is to invoke few methods in your component, then there is no need to implement other interfaces, IDispatch is enough (although ISupportErroInfo could be useful for error reporting) Whether to mark it "safe for scripting" or not is up to you. If you won't, the IE behavour will depend on IE security setting "SCript ActiveX controls marked safe for scripting" : "disable", "prompt", "enable" Edward