Hi boost users, I have a question regarding the best use of the boost pools and shared_ptr Consider the following tree node object. class A { public: typedef boost::shared_ptr< A > SPA; typedef std::vector< SPA > SPAVec; SPAVec children; }; This class allows me to have a tree or trees where some of the nodes may be shared. E.g. // tree1 tree2 // X Z // Y Y Y X // Y Y Logically the root of tree1, X has two children Y and Y but physically of course I only have one copy of Y in memory. Other trees, e.g. tree2 can also share these branches. Now assume I'm also very often constructing and destroying nodes. An object pool is an obvious optimisation to try out. However shared_ptr would need to call object_pool::destruct() instead of delete when it really wants to destroy the object. Or singleton_pool::free() but this causes more difficulties for me because I want to control the lifetime of the pool separately for each instance of my objects which are working on these trees. Can anyone offer a nice solution to this problem? kind regards, James Swift.