Wikipedia defines a Multiple Listing Service as 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.

The purpose of the MLS is to enable the efficient distribution of information so that, when a real estate licensee is introduced to a potential home buyer, he/she may search the MLS system and retrieve information about all homes for sale in a given area or price range, whether under a listing contract by that licensee's brokerage or by all participating brokers.

In North America, the MLS systems are governed by private entities, and the rules are set by those entities with no state or federal oversight, beyond any individual state rules regarding real estate. MLS systems set their own rules for membership, access, and sharing of information, and board-owned associations are subject to nationwide rules laid down by the National Association of REALTORS® (NAR) or Certified Real Estate Agents (CREA). An MLS may be owned and operated by a real estate company, a county or regional real estate Board of REALTORS® or Association of REALTORS®, a not-for-profit association, or by a trade association. Membership of the MLS is generally considered to be essential to the practice of real estate brokerage.

Alaska Multiple Listing Service, Inc., commonly known as Alaska MLS or AK MLS, is a not-for-profit association that has been serving the real estate industry in Anchorage since 1956 and available statewide since 1996.

By agreeing to operate under a standard set of rules, several visionary real estate brokers created Multiple Listing Service, providing for a competitive, but efficient and uniquely cooperative marketplace. The Anchorage Board of REALTORS® purchased the service on October 1, 1969 from the former owners. Nine individuals, being members of that Board, loaned the money for the purchase of the company ($20,000) and this loan was repaid during the first year of business including 6% interest. The service became incorporated and functioned as REALTOR MLS, Inc. with all members being required to be members of the Anchorage Board of REALTORS®.

In June 1976, due to various reasons, the members elected to become an independent entity called Multiple Listing Service, Inc. In 2002, the members agreed to change the corporate name to Alaska Multiple Listing Service, Inc. and redesign the corporate logo. These changes were made to better represent the customers and expanded service area of the association as well as to improve trademark protection. In 2003, the logo was re-designed once again to meet the additional needs of a new association marketing program and website re-design.

The association was originally intended to operate as a non-profit and was accepted as such when the State of Alaska incorporated it in 1969. However, according to the Federal tax laws, multiple listing services are not considered non-profit, therefore Alaska MLS, Inc. operates as a taxed not-for-profit 501 (c)(6) association.

Alaska MLS experienced rapid member and financial growth until the mid 1980's when it experienced tremendous losses due to a statewide economic downturn. Thanks to the efforts of dedicated Boards of Directors and the support of the membership, the service recovered as a more resourceful and efficient association.

By the end of the 1990's, the association was again in a challenging state of flux. As a result of changing member needs, technology and economics, the Alaska MLS information database and all auxiliary internal systems were completely modernized. The Alaska MLS database became compatible with not only desktop software, but also with the latest Internet browser based systems, palm units, and third party software vendors. On a statewide level, Alaska MLS participation continues to grow with Alaska MLS as the sole MLS provider for all of South-Central Alaska.

After a strategic planning session and service needs poll were held in 2003, the Board of Directors determined that introducing the membership to an Internet-based MLS system would serve as a flexible solution to meeting the current and future needs of Participants. In December 2005, the software-based WyldFyre MLS system was replaced with the Internet-based flexmls^TM System.

Throughout the years, AK MLS services have consistently improved. The Association has grown from five members who shared loose-leaf listings in the 50's, to the 336 members, associate members, and statewide data subscribers who represent approximately 1,850 real estate licensees and appraisers. Together they share the sophisticated databases and MLS business tools of today.