Yes, we archive all logos and make off-site backups. If you ever loose your logo files, you can be sure that we will be able to dig your logo out, dust it off and send you a fresh set of logo files.

This is also handy for when you need changes to the logo. Changes after the finalization of the logo won't be free, but because we have the logo on file we don't have to redesign from scratch so changes will cost a lot less than the original design work - and a lot less than if you go to another designer for the changes :)