Hi, I've just tried to measure performance of Boost.Function and Boost.Signals using the following simple program: #include <boost/function.hpp> #include <boost/signals.hpp> using namespace std; void do_nothing() {} int main() { boost::function<void (void)> f = do_nothing; void (*pf)(void) = &do_nothing; boost::signal<void (void)> s; s.connect(&do_nothing); for(int i = 0; i < 10000000; ++i) s(); return 0; } and trying calls to 's()', 'pf()' and 'f()'. The timings are, on an Athlon 1700 with g++ 3.3.5 and -O3: Function pointer: 0.05 secs Boost.Function: 0.2 secs Boost.Signals: 9.8 secs Boost.Function is 4 times slower than function pointer, which seems decent for me (not that I mind further improvement). But Boost.Signals is nearly 50 times slower that Boost.Function, and nearly 200 times slower than function pointer. Any chance this will be improved? Say, I don't care about combining the results of signals invocation, or any connection tracking -- I just want to use boost::signals as more convenient variant of vector<boost::function>. Is it possible to have some preprocessor define that throws away all advanced functionality? Or a base class, say "lightweight_signal" that has only basics? TIA, Volodya