Nance; main reason for not using disk compression is performance. It slows down the whole system (regardless of what MicroMonkies might say), every time you call a compressed file it has to be uncompressed to work with it then recompressed when your done with it. On top of slow down there are also resources involved in the decompression/re-compression. Also take note that HD space limits do calculate the "used space" based on Non-compressed data, not on the compressed status. Say a user has a file restriction of 50Meg on a hard drive; that is 50Meg Un-compressed, not 50Meg after compression (talking Windows here, don't know MAC) IMO, it's ok for standard office jocky machines but not sutable for any machine that needs power and speed. On the other hand, with some of the more powerful machines today, loaded with memory and plenty of disk space then it may not (in most cases) cause much issues.