I usually make a copy and rename the copy with the date and time last saved (ie: myfile 02082007 1425.mdb). Then make a note of the name, date and what was added (design changes) in a log I keep. Then LATER if I find something is amiss I have an idea of where I was in each copy. I've also gotten in the habit of making and archiving a copy BEFORE and AFTER I make changes as well. So if a form corrupts (and this HAS happened, but rarely) I have a place to get a good copy from.