Hi Anthony, N2497 includes the following thread constructor overloadings template <class F> explicit thread(F f); template <class F, class ...Args> thread(F&& f, Args&&... args); void swap(thread&&); Boost.Threads try to conforms to N2497 as muh as possible. Boost.Threads defines already #ifdef BOOST_HAS_RVALUE_REFS template <class F> thread(F&& f); #else #ifdef BOOST_NO_SFINAE template <class F> explicit thread(F f); #else template <class F>explicit thread(F f, typename disable_if< boost::is_convertible<F&, detail::thread_move_t<F> >, dummy* >::type=0); #endif template <class F>explicit thread(detail::thread_move_t<F> f); template <class F,class ...Args> thread(F f, Args... args) I have some questions. Is there any deep raison for which template <class F> explicit thread(F f); should not always be defined? Is there any deep raison to emulate template <class F,class ...Args> thread(F f, Args... args) instead of template <class F,class ...Args> thread(F&& f, Args... args) Could template <class F, class ...Args> thread(F&& f, Args&&... args); rally be emulated? You provide 'void swap(thread&)'. Could 'void swap(thread&&)' be emulated? Do you know if the following overloadings are taken in account by the boost::swap utility? void swap(thread& x, thread& y); void swap(thread&& x, thread& y); void swap(thread& x, thread&& y); Thanks in advance, Vicente