Go to menu item Files -> Set Password..., and assign as strong password as possible to assure maximum safety. Once the password is assigned nobody will be able to view your data even if the .ddb file will be placed on public locations.

It has probably been discussed before, but I looked in the forum back to 2012 and didn't see it. However I also did not search for it. I would like to see the Database encrypted, especially as I use it shared from Skydrive. With the NSA snooping on everything this could be big business, to have encryption. :ugeek: