You can have as many TimeTracker documents open as you want at the same time (as many as memory permits).  For example, let's say you're working on “Johnson,” and you get a phone call from Mr Jones.  You pause the Johnson document and start the Mr Jones document.  Phone call ends, you stop the Mr Jones document, and resume the Johnson document.

Please review the rest of this manual for more information on how to use TimeTracker.  It wouldn't take long.