To most people, the term “REALTOR” is a term that is synonymous with "real estate agent".  This, however, is a common misconception.  “REALTOR” is actually a trademarked term that only applies to members of the National Association of REALTORS.

By joining the REALTOR organization, members are held to the highest professional and ethical standards, and are expected to adhere to NAR’s strict Code of Ethics addressing duties and obligations to their clients, the public and the industry. Working with a REALTOR as opposed to a non-member licensee gives buyers and sellers reassurance that their real estate professional is required to maintain a high standard of professional conduct, and looks out for their best interest.

National Association of REALTORS Code of Ethics (latest version)

NAR's Code of Ethics/Professional Standards Policies (REALTOR.org login required)