Alright I've been through the mailing list a few times, and thanks to Ovanes for the help on getting some of the mpl stuff working. Here's what I've got working so far. I built a vector100.hpp and placed it in the boost\mpl\vector and added the following to my header. #define BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS #define BOOST_MPL_LIMIT_VECTOR_SIZE 100 #include "boost/mpl/vector.hpp" #undef BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS #undef BOOST_MPL_LIMIT_VECTOR_SIZE Great everything works great, except for the fact that it takes an extra long time to compile. So following some threads on the list, I'd like to pregenerate a header file with the definitions for the vector that takes 100 elements. Placed the vector100.cpp in the \libs\mpl\preprocessed\vector and ran the preproces.py and got the vector100.hpp file generated in boost\mpl\vector\aux_\preprocessed\plain. Everthing seems like I'm heading in the right direction to get it proprocessed. So know what do I do to get it included in the same way as the previous code? I've tried including the new header directly and playing around with various macros to get it to be included, but no dice so far. Is there a way to have the preprocessing scripts regenerate the vector.hpp in boost\mpl\aux_\preprocessed\plain? So that I can use boost::mpl::vector instead of a version with the number of parameters in it, because that's varies dramatically throughout how this code is being used and would be a major pain. -Neal