The Associative Containers project can refer also to Shmem, since Shmem has implemented the full ordered vector family (flat_map, flat_set, flat_multimap and flat_multiset) for shared memory (these containers work also with std::allocator). Another option is to take those containers out of Shmem (they have minor dependencies with Shmem framework) and present them as general purpose containers that also are useful for shared memory/memory mapped files. Like boost::unordered_xxx family, I would like to have just one container in Boost without duplicating it in other libraries. The bad news is that Shmem flat_xxx containers are not documented, but it's not difficult to do it since they have the same interface as std::map/set family. The hard part is the portability to non-conforming compilers like VC6, but I think there are utilities in Boost to workaround these problems. Regards, Ion