Hi all, Here''s the problem. A particle effect object aggregates a number of particle objects. The effect will last for a certain amount of time, then it has to be destroyed. talking OO what''s the best way to do this (to deallocate the effect object + resources). One solution is to let the particle effect object inform the rendering window that it''s done (the effect has ended) and the rendering window then will be reponsible for doing the deallocations. Is there any better way. I am actually looking for a way to make the effect object itself responsible for its own life cycle. Thanks in advance, IDispatch