What is a Master Key System, you might ask? It is a key system that we custom design for a customer with the intention of giving top management of a company a single key that works every door, while giving employees keys that may only work on an individual door. You will find these in most hospitals, schools, nursing homes and large businesses. However, since they are customized for your specific needs, you may want to inquire about them regardless of the size of your business. The ultimate goal of a master key system is that management, maintenance, housekeeping etc. carry as few keys as possible to gain access to wherever they need to go within a building.