Hi Can I store boost::mutex'es in a map using the following constuct typedef boost::shared_ptr<boost::mutex> MutexPtr; typedef map< std::string, MutexPtr> MutexMap; MutextMap mmap; mmap["foo"] = MutexPtr( new boost::mutex ); I'm not sure that this is safe to do - the boost::mutex is boost::noncopyable which might indicate that there could be a potentional problem. Thanks in advance