A fundamental truth of building security is that one misplaced key constitutes a crack in the armor that protects a space from unwelcome intruders. Imagine the headaches for administrators and security officials at a large university, where thousands of keys that are distributed to students and staff never find their way back to school officials. For many years, the solution to this problem has been keyless access-control systems that use swipe or contactless cards to allow authorized users into a campus facility. As technology improves and card systems can be equipped with more functions, the appeal of card-based access-control systems has grown for administrators and facility managers. Some large university campuses with many buildings have installed keyless access-control systems at some of their facilities, but often individual departments have acquired different and incompatible access-control systems. Colorado State University in Fort Collins is one of the campuses that over time has acquired a mix of lock-and-key systems and separate access-control systems at its various buildings.