The National Association of Realtors (NAR) is a trade organization that represents the interests of real estate professionals in the United States. State Realtor associations like IAR and local Realtor associations are typically affiliated with the NAR and adopt many of its policies and guidelines. These boards also have their own leadership and may have slightly different rules and regulations depending on the state or local area.
Multiple Listing Services (MLS) are databases of real estate listings that are maintained by the state and local boards. In many cases the local association is the owner of the MLS company, or several local associations each have a position on the MLS company's board of directors. These databases allow real estate professionals to view and share information about properties for sale in a particular area, and are typically only available to members of the board.
The NAR, state boards and local boards provide a range of services and resources to their members, including professional development and training opportunities, as well as access to the MLS. They also lobby on behalf of the real estate industry at the national, state, and local levels, and work to promote the value of professional representation in real estate transactions.
All of these entities (NAR, state boards, local boards and multiple listing services) work together in the larger goal of helping real estate professionals and their clients by providing industry standards, education, representation and assisting the buying and selling process.
In addition, they collaborate and support each other by agreeing on policies, rules and regulations that are then adopted by all entities, with some variations depending on the state or location. This allows for a consistent and streamlined real estate industry that benefits everyone involved.
A real estate agent must first join a local Realtor Association and pay their annual dues. The dues include membership dues to the State Realtor Association and the Nation Association of Realtors. Once their membership in all three organizations has been verified, the National Association of Realtors issues a NERD's number which is a unique membership ID used in all the associations. Once a NERD's number is issued, the agent can then join the local MLS by paying MLS access dues. The real estate agent is now a Realtor with access to the basic Realtor tools.