Hi all, I'm probably not adding any new knowledge to this post, but I've been tracking this discussion as I too am very eager to install Vista on my new laptop (coming soon) with Program Files and User Profiles on separate partitions. After reading all your responses, I *think* this might be the closest I could get to have ProgramFiles, ProgramData and Users on their own separate partitions. Let me stress that I haven't tested this yet so I wouldn't recommend anyone try this until someone's confirmed it works. 1. Use WSIM to create an answer file to install ProgramData and ProgramFiles on their own partitions. 2. Install Vista. 3. Boot into Vista and XCOPY C:\Program Files to another partition. XCOPY has options to preserve permissions and file ownerships which I'm not 100% a copy in Windows Explorer does. 4. Change the keys in HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\* to point to the new locations (including Common Files. 5. At this point it's probably worth a reboot to see if the programs are working properly. 6. As someone mentioned before, some default Windows programs are installed with a reference to "%systemdrive%\Program Files" so I'll probably have to manually change some links. On a fresh install of Vista, there shouldn't be too many. Also this step is optional because of step 10 (see later). 7. Again, reboot and try some default apps like WMP. 8. Boot into a BartPE CD and *rename* "C:\Program Files" to something else (I wouldn't delete it yet). This step is probably necessary because if you are in Vista, some files will be in use and you will not be able to touch the folder. 9. Boot back into Vista and make sure some programs work. It's probably not possible to test every single program in Windows so I recommend step 10. 10. Create a symbollic link on C: to your new Program Files, Program Data and Users folders on other partitions. The reasoning for this is, if I missed anything in step 6, at least C:\Program Files exists and links to a location that contains the actual files. Also, you never know what naughty developers might hardcode paths in their setup files. 11. Use Vista for a few weeks and when I'm happy with the system, delete the renamed Program Files folder on C:. If I've missed anything, please do let me know. After I've tried this on my laptop, I'll let everyone know my results.