"This link worked yesterday – why doesn't it work now?" "Will all of our local MARC fields migrate when we change catalogs?" When it comes to integrated library systems and electronic resources platforms, the one constant is change. Whether it's migrating all your MARC records to a new catalog system or updating URLs when an e-book vendor changes their platform, most library staff members encounter a migration at least once in their career. These processes can be daunting, but they don’t have to be scary.