Hi all, having a night asleep due to jet lag I have hacked another object factory code. Download factory_16_10_2007.zip from Boost Vault or directly with: http://tinyurl.com/yq7cap This new object factory is IMHO much more powerful and has a much better design then the previous one. It is based on complete different ideas and has all the features of the previous one with added implicit argument conversions, so that asking the factory for an object now mimics 100% what you would have calling the object c'tor directly. It is an integration of the new 'overload' utility with Tobias boost::factory (get from Vault) As 'overload' utility I used mine (original code by Joel) not Marco Cecchetti' s one because I only needed a very trimmed down version, I have trimmed down also mine that was already very small !! There are no stored variables or member data anywhere. The factory itsef is just a bunch of typedefs and few static member functions. I think code is small and nice for the task and further polishing could be expected. Previous simple_factory.zip code has been retired from Boost Vault to not pollute the namespace ;-) Marco