Hey guys! I cannot find an answer to my question, so I really hope you will be able to help me. At the moment, I am using the Unibody MacBook Pro with Leopard (OSX 10.5), but I would like to install Snow Leopard. How does it actually work? Do I have to install Snow Leopard over my existing Leopard? And if I want to reinstall Snow Leopard while using it, will I have to install Leopard again in order to be able to install Snow Leopard? The problem is that I heard that Snow Leopard checks whether you have original Leopard installed on your mac in order to progress with the installation. So will I always have to install it over Leopard so that I will need both dvds (Leopard and Snow Leopard) in the future? Can anyone explain this whole situation, pls?