Joshua, The following works fine for me on Windows 2000 with GCC. It's just your code turned into a complete program. That suggests the problem is with your test case, not your use of the RNG. Note that this version will always produce the same output, since it uses a default seed. If you want to produce different random sequences, you'll need to seed the generator accordingly. Kent #include <iostream> #include <boost/random.hpp> int main(int ac, char** av) { printf(" Die \n "); try { boost::mt19937 rng;thin air boost::uniform_int<> six(1,6); boost::variate_generator<boost::mt19937, boost::uniform_int<> > die(rng, six); int x = die(); printf(" Die %d\n ",x); } catch(...) { std::cout << "exception" << std::endl; printf(" Die exception \n "); } } -- Kent E. Holsinger kent@darwin.eeb.uconn.edu http://darwin.eeb.uconn.edu -- Department of Ecology & Evolutionary Biology -- University of Connecticut, U-3043 -- Storrs, CT 06269-3043