If you would like to add custom Python modules for use in FaceFX Studio, place them here. The modules must correspond to the version of Python that FaceFX Studio uses (you can see this version information in the Console when starting up FaceFX Studio). Python can't load .pyd files from inside zip archives, so be aware of that (indeed this is the reason that this site-packages directory exists here). Make sure you also add the .pth files and any other files the module drops in your own site-packages folder. For example, suppose I wanted to use the Python Imaging Library (PIL) inside of FaceFX Studio. Here is how I'd do that: 1) Make sure I have the same version of Python installed on my local machine that Studio uses. At the time of this writing, that is Python 2.6.5. So I have C:\Python26 which has my Python 2.6.5 installation there. 2) Make sure I have installed the PIL module on my system (most module installers will look in the registry to find your Python installation and install into it). In this case, PIL's installer detected my Python 2.6.5 installation in C:\Python26 and installed itself into C:\Python26\Lib\site-packages. 3) After PIL is installed, in C:\Python26\Lib\site-packages I see a PIL directory and a PIL.pth file. I copy both to Studio's Python26\site-packages folder in Studio's application directory. Be on the lookout for files the installer put in the root of the site-packages directory (like PIL.pth in this case), and copy them as well. 4) Now I have access to PIL from inside Studio. To verify, I can do from PIL import Image in Studio's Python shell. You don't need to restart Studio for the addition of new modules to take effect.