The American Association of Orthodontists is the national organization of dental specialists who limit their practice to orthodontics and dentofacial orthopedics. Founded in 1900, the AAO is the oldest and largest dental specialty organization in the United States and Canada. To date, the AAO has more than 14,600 members, including more than 2,000 international members from outside North America. This membership consists of approximately 94 percent of all orthodontists who currently practice in the United States.

The AAO is dedicated to advancing the art and science of orthodontics and dentofacial orthopedics, improving the health of the public by promoting quality orthodontic care, and supporting the successful practice of orthodontics. All members must meet the specialty educational requirements as defined by the Commission on Dental Education of the American Dental Association.

The American Dental Association has recognized that "specialists are necessary to protect the public, nurture the art and science of dentistry, and improve the quality of care."