i've written a little test to see if i've installed boost properly on my mac #include <boost/thread.hpp> #include <boost/shared_ptr.hpp> #include <boost/bind.hpp> #include <iostream> void simple_thread( boost::shared_ptr<int> p ) { std::cout << (*p) << std::endl; } int main (int argc, char * const argv[]) { boost::thread_group threads; for ( int i = 0 ; i < 5 ; i++ ) { boost::shared_ptr<int> p( new int(i) ); threads.create_thread( boost::bind( &simple_thread, p ) ); } threads.join_all( ); return 0; } in xcode (a C++ Tool project) this compiles fine, however on runtime i get the following error: ZeroLink: unknown symbol '__ZN5boost12thread_groupC1Ev' boost_test has exited due to signal 6 (SIGABRT). using g++ i get the following errors (ignoring warnings) g++ main.cpp -o boost_test -I/usr/local/include/boost-1_31 -L/usr/local/lib ld: Undefined symbols: boost::thread_group::create_thread(boost::function0<void, std::allocator<boost::function_base> > const&) boost::thread_group::join_all() boost::thread_group::thread_group[in-charge]() boost::thread_group::~thread_group [in-charge]() i originally built boost using the command line sudo bjam -sTOOLS=darwin install can anyone help me with what i am missing here? thanks --Tristan