Shalom A possibly easier to read version of this note is here - http://www.webebenezer.net/uncontainers_mar182008 I'm happy to report that we have added serialization support for the following types from the recently accepted Unordered Containers library: unordered_set, unordered_multiset, unordered_map and unordered_multimap. I recall past discussion of names for these containers. I'm of the opinion there is room for improvement in this area and Erik Wikström points out on c.l.c++ that the containers are "ordered by the hash of the key." We are also interested in supporting the Intrusive library. It would be helpful to hear if there are trends developing in the way people use that library. Brian Wood Ebenezer Enterprises www.webebenezer.net