Anyone else agree this is a problem? I was trying to compile this simple program: #include <boost/numeric/ublas/vector_sparse.hpp> #include <boost/numeric/ublas/io.hpp> #include <iostream> int main(int argc, char** argv) { using namespace boost::numeric::ublas; mapped_vector<double> v(3,3); for ( unsigned i = 0; i < v.size(); ++i ) v(i) = i; std::cout << v << std::endl; return 0; } and the include hierarchy ends up including serialization/utility.hpp. This file uses the template mpl::and_, so I think it should include xpressive/xpressive.hpp. Sancho