Hi, boost vault (section 'Concurrent Programming' - http://www.boostpro.com/vault/) contains boost.task. It replaces boost.threadpool and provides a framework for parallel execution of tasks (launching task in the current thread, in a new thread, as sub-task or in a pool of threads). The code looks someting like this: std::string echo( std::string const& msg) { return msg; } void main() { boost::task::handle< std::string > h( boost::task::async( boost::task::new_thread(), boost::task::make_task( echo, "Hello World!") ) ); std::cout << h.get() << std::endl; } or long fibonacci_fn( long n) { if ( n == 0) return 0; if ( n == 1) return 1; long k1( 1), k2( 0); for ( int i( 2); i <= n; ++i) { long tmp( k1); k1 = k1 + k2; k2 = tmp; } return k1; } void main() { std::cout << "worker-threads running in default-pool == "; std::cout << boost::task::default_pool().size() << "\n"; boost::task::handle< long > h1( boost::task::async( boost::task::default_pool(), boost::task::make_task( fibonacci_fn, 10) ) ); boost::task::handle< long > h2( boost::task::async( boost::task::default_pool(), boost::task::make_task( fibonacci_fn, 5) ) ); std::cout << "fibonacci(10) == " << h1.get() << "\n"; std::cout << "fibonacci(5) == " << h2.get() << std::endl; } best regards, Oliver