As was the case with QuarkXPress 7.x, you are allowed to install QuarkXPress 8 on two machines at the same time. This is called dual licensing. What is new with the release of QuarkXPress 8 and QuarkXPress 9 is that these installations can be across platforms AND can be run concurrently. For example, if you are running Windows via VMWare or Parallels on your Mac, you can install and run QuarkXPress 8 at the same time in the Macintosh OS environment.