It's not just memory drag -- it reaches the point that Poser 5 stops working. For example, I'll open a file, and it will act like the file is open, but I won't see it. (Nothing in the document window, or no document window at all. Close Poser, open the file again, and everything's fine.) Or I'll try to apply a pose, change a morph dial, or apply a prop, and nothing will happen. Again, closing Poser and getting back in fixes it. I don't think it's a Windows XP problem, because most of the time, I can run for weeks without re-booting. The only program besides Poser 5 that needs shutting down occasionally to fix memory issues is AOL 9. :-P FWIW, I've noticed it's mostly a problem when I'm working in very large files. For example, using several V3s, M3s, the MilCat, and textured mansion. Every once in a while I had to shut Poser down, or it would just stop working.