High Quality Content by WIKIPEDIA articles! The American Osteopathic Association (AOA) is the representative member organization for the over 78,000 osteopathic medical physicians (D.O.s) in the United States. The organization promotes public health, encourages academic scientific research, serves as the primary certifying body for D.O.s overseeing 18 certifying boards, is the accrediting agency for osteopathic medical schools through its Commission on Osteopathic College Accreditation, and has federal authority to accredit hospitals and other health care facilities.