The American College of Surgeons, located in Chicago, Illinois is a scientific and educational association of surgeons that was founded in 1913 to improve the quality of care for the surgical patient by setting high standards for surgical education and practice.

Members of the American College of Surgeons are referred to as "Fellows." The letters FACS (Fellow, American College of Surgeons) after a surgeon's name mean that the surgeon's education and training, professional qualifications, surgical competence, and ethical conduct have passed a rigorous evaluation, and have been found to be consistent with the high standards established and demanded by the College.

There is also another category of membership known as "Associate Fellow." This category was established to provide an opportunity for surgeons who are beginning surgical practice and who meet specific requirements to assume an active role in the College at an early stage in their careers.

The College currently has more than 64,000 Fellows, including more than 3,700 Fellows in other countries, making it the largest organization of surgeons in the world. There are presently more than 5,000 Associate Fellows.