If you are using Visual Studio Team System Beta 2 and using the profiler on unit tests, there is a small issue that you should be aware of. Currently the IDE does not stop you from right clicking on a running unit test and clicking “Create Performance Session.” However, doing this will get you into a bad state. This issue has long since been cleared up for the final release, but just remember, for Beta 2 don’t try to profile a currently running unit test from the IDE.