A Multiple Listing Service (MLS) (also Multiple Listing System or Multiple Listings Service) is a group of private databases which allows real estate brokers representing sellers under a listing contract to widely share information about properties with real estate brokers who may represent potential buyers or wish to cooperate with a seller's broker in finding a buyer for the property. There is no single authoritative "MLS", and no universal data format. The many local and private databases--some of which are controlled by single associations of realtors or groupings of associations (which represent all brokers within a given community or geographical area) or by real estate brokers--are collectively referred to as the MLS because of their reciprocal access agreements.