I was implementing IDispatch, and I've run into the use of STDMETHODCALLTYPE which is equivalent to __stdcall. My question is, does the use of STDMETHODCALLTYPE serve any particular purpose other than renaming __stdcall? I mean, maybe in the future STDMETHODCALLTYPE will map to god knows what else, and using STDMETHODCALLTYPE would then keep your code from breaking. Because, otherwise, I see it like this: I like __stdcall. It's neat, it's specific, it's a pretty recallable thing. But 8, 20, 1000 typedefs that just rename __stdcall seems to do nothing other than add memorization overhead to the process. So I want to know if anyone out there knows of a specific reason why STDMETHODCALLTYPE began being used, a reason beyond just identifier massaging.