Not to argue with borisb,., but... Local backup is important regardless. Also keep all the PDF, epub, etc in separate folder (I have it on USB flash, most of my files are non DRM) and add papers to library only for markup purposes. However if you do local backup so far there is no way to move your backup library to another device. I was only able to open it through PC and move journal files and add them to new library on another PE. also PDF and other documents, but all tags and markup is gone. However through Entourage server archive I was able to merge all files with markup and tags to another PE (mind I don't have a lot yet, so it went rather quickly). So if you need to move some files from device to device right now, you can use Achieve, just do not rely on it exclusively as future of Entourage servers is uncertain... And obviously you need both devices registered under same account...