1. Save the current session: :mks! ~/v/project1.vim 2. Quit vim :xa 3. Restart with a different session file: vim -S ~/v/project2.vim I was exiting and re-opening vim because if I just loaded the second project file, a list of both project buffers would appear in my buffer list. That was not what I wanted -- I wanted to replace the first buffer list completely wtih the second. There is a simple way to do this. At the top of a session file, add this: 1,999bdelete :so ~/v/project2.vim