The Ontario Medical Association (OMA) represents the political, clinical and economic interests of the province's medical profession. Practicing physicians, residents, and students enrolled in any of the five Ontario faculties of medicine are eligible for OMA membership.

Founded in 1880 as a voluntary association of the province's physicians, the OMA as from its beginning played a vital role in the development and promotion of health-care services across Ontario.

Today, the OMA represents Ontario's physicians. It is governed by a Council composed of over 250 delegates, representing 78 territorial divisions or branch societies, and by the Association's Board of Directors. The Board consists of representatives from 11 districts, a representative of the six faculties of medicine in Ontario, and five Directors elected by Council.

Between meetings of Council, the Board represents the OMA's governing body and members in all business affairs, and exercises the rights and powers of the Association. From among its members, the Board elects the Association's Executive Committee, which is responsible for liaison with government and other organizations.

The OMA's clinical sections represent physicians sharing a common specialty or area of clinical or practice interest. Section activity has increased in recent years, thereby enhancing the profession's ability to shape decision-making and ensure that patient care remains foremost in policy decisions.

A number of OMA health policy committees bring together experts from across the province to address important clinical and legislative issues facing physicians and patients. Programs, discussion papers, and educational material arising from the work of the OMA's health policy committees are important components of the medical profession's contribution to the development of public policy on health care.

OMA staff implement policy developed by Council and the Board of Directors.
Headed by the Association's Chief Executive Officer, OMA staff include professionals in the fields of administration, practice management, finance, health policy, legal services, economics, computer technology, insurance, hospital services, laboratory proficiency testing, medical services, physician health, public affairs, and communications.