1. Right-click any file and choose "CVS -> Preferences". 2. In the TortoiseCVS window, choose the "Tools" tab. 3. Place the following in the "Diff Application" text box (adjust for your Vim install location): C:\Program Files\Vim\vim70\gvim.exe 4. Place the following in the "Two-way diff parameters" text box: -d "%1" "%2" Now you should be able to right-click a CVS-controlled file, choose the "CVS diff" option and view results in Gvim. Any additional Gvim parameters should only appear in the "Two-way diff parameters" text box, not the "Diff application" text box.