Multiple Listing, or ML, is the phrase used to describe the cooperative arrangement among all realtors who belong to the same, local Board of Realtors. This agreement allows realtors from all companies to share access to the properties that have been put up for sale so that agents and brokers from one company can easily access all properties listed by all the other brokers in the event they are working with a buyer. Typically, the seller of a property will pay one real estate fee that is shared by both the realtor that is working for the seller and the realtor that is working for the buyer.
The real estate companies manage this system through governance by a Board of Directors selected from the participating real estate companies. There are rules governing behavior and fair play within the system as well as a mechanism for disciplining those who do not comply with the rules set up for sharing access to all listings.