If you install XP after Vista, the NT boot loader will overwrite the new windows boot loader, effectively rendering Vista unbootable. You can, however, remedy this problem by following these instructions from within XP after the successful installation. Reboot and you should find both OSes to be fully functional.
Hope this helps,
John
It is time for me to upgrade from Windows 98!! I know I am able to install Vista on a machine with XP and run the 2 operating systems. What I would like to do, because of some special pricing offers in my area, is to buy a Vista loaded machine and then install a full version of XP Pro on the same machine. Is there any problem with doing this, considering that it would appear to be going in the reverse direction, but it makes sense for me (I think.

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