Pro Tools 4.0 has a "Record Safe" function similar to putting a track into Safe Mode on a professional multitrack deck. As you no longer have to hold the shift key to add tracks to a group of tracks you'd like to record to, this may help prevent accidental destructive recording over desired material. Simply hold down the Command key and select the Rec button on any track. This will gray-out the button until you reverse the procedure.Note: Option+Command puts all tracks into Record Safe.