Hi, I am sure this is due to some trivial mistake; the statement to create a pointer member function insert of multi_index container fails in the following code: typedef multi_index_container< std::pair<int,int>, indexed_by< ordered_unique<member<pair<int,int>, int, &pair<int, int>::first> > > > mic; std::pair<mic_index::iterator, bool> (mic_index::*fn)(pair<int,int>) = &mic_index::insert; //compile error The error is due to mismatch in signature as given in the error: std::pair<boost::multi_index::detail::bidir_node_iterator<boost::multi_index::detail::ordered_index_node<boost::multi_index::detail::index_node_base<std::pair<int, int>, ... std::pair<boost::multi_index::detail::bidir_node_iterator<boost::multi_index::detail::ordered_index_node<typename SuperMeta::type::node_type> >, bool>... If need be I can post full error message. Appreciate any suggestions. Thanks sandeep