Hello Ju@ncho, There are two ways you can achieve your design : 1. By declaring the object properties "FramesOfReference" and "Series" as of their individual interface types (e.g. IFramesOfReference, ISeries, respectively) : interface IStudy : IDispatch { [propget, id(1), helpstring("property FramesOfReference")] HRESULT FramesOfReference([out, retval] IFramesOfReference** pVal); [propput, id(1), helpstring("property FramesOfReference")] HRESULT FramesOfReference([in] IFramesOfReference* newVal); } interface IFramesOfReference : IDispatch { [propget, id(1), helpstring("property Series")] HRESULT Series([out, retval] ISeries** pVal); [propput, id(1), helpstring("property Series")] HRESULT Series([in] ISeries* newVal); } 2. By delaring the object properties as of type VARIANT : interface IStudy : IDispatch { [propget, id(1), helpstring("property FramesOfReference")] HRESULT FramesOfReference([out, retval] VARIANT *pVal); [propput, id(1), helpstring("property FramesOfReference")] HRESULT FramesOfReference([in] VARIANT newVal); }; interface IFramesOfReference : IDispatch { [propget, id(1), helpstring("property Series")] HRESULT Series([out, retval] VARIANT *pVal); [propput, id(1), helpstring("property Series")] HRESULT Series([in] VARIANT newVal); }; I have written a set of sample codes. Email me : bio_lim_2004@yahoo.com and I will send it to you. Best Regards, - Bio.

may be you can have a look at Microsoft's Asyncronous block from MS patterns and practices. not sure. cheers varun.y.sharma@gmail.com

Ju@ncho wrote: Hi! I need to pass a series of raw bitmaps in memory from c++ to VB (and then from VB to c++). Does anyone know how to do this? I am trying to encapsulate all the functions in a ActiveX, so i think i should pass my raw unmanaged c++ data to an Interface like IPicture or something like that. You can use the function OleCreatePictureIndirect to create an IPicture wrapper around a bitmap. I think there are members of IPicture that allow you to render it to a bitmap to do the reverse. Nathan