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ACP Facts


The American College of Physicians (ACP) is a national organization of internal medicine physicians – specialists who apply scientific knowledge and clinical expertise to the diagnosis, treatment, and compassionate care of adults across the spectrum from health to complex illness. Internal medicine specialists are the largest group of practicing physicians in the U.S. and deliver much of the primary care that is provided. They are especially well-trained in the diagnosis of puzzling medical problems, in the ongoing care of complicated illnesses, and in caring for patients with more than one disease. Internal medicine physicians not only treat disease but also coordinate health care and play a critical role in preventing disease and promoting health and well-being.

Internal Medicine Physicians and Subspecialists

An M.D. or D.O. who completes a three-year internal medicine residency program is an internal medicine physician or internist. The general internist is an expert in the general care of the adult but also may have special areas of expertise. A subspecialty internist is an internal medicine physician with one to three years of additional training in a particular organ (nephrology/kidney), system (endocrinology/glands), or age group (geriatrics). Some internal medicine physicians practice a combination of both general and subspecialty medicine.

Mission and History

The ACP mission is to enhance the quality and effectiveness of health care by fostering excellence and professionalism in the practice of medicine. ACP was founded in 1915 to promote the science and practice of medicine. In 1998, ACP merged with the American Society of Internal Medicine (ASIM), which was established in 1956 to study economic aspects of medicine.


With 160,000 members, ACP is the largest medical specialty organization and second-largest physician group in the United States. ACP provides information and advocacy for its members as they practice internal medicine and related subspecialties such as cardiology and gastroenterology. ACP members are also involved in medical education, research, and administration.

Levels of ACP membership are Medical Student, Associate, Member, Fellow (FACP), Honorary Fellow, and those elected to receive Mastership (MACP). Fellowship and Mastership recognize achievements and outstanding contributions in internal medicine.

ACP Publications

Annals of Internal Medicine is one of the top medical journals in the world. ACP JournalWise summarizes the most important medical articles from more than 120 journals. ACP Internist is an award-winning semi-monthly newspaper for internal medicine physicians, while ACP Hospitalist is written for those in hospital practice. The ACP Advocate is a bi-weekly e-newsletter that provides ACP members with news about critical public policy and regulatory issues affecting internal medicine and patient care. 


The ACP Washington, D.C., office monitors and responds to policy issues that affect public health and the practice of medicine. Activities include development of policy statements and communication with legislative and administrative sectors of government.

The Center for Ethics and Professionalism seeks to advance physician and public understanding of ethics and professionalism issues in the practice of medicine in order to enhance patient care by promoting the highest ethical standards.

Education and Information Resources

ACP supports the optimal practice of medicine by providing opportunities for continuing medical education. ACP medical education programs include the development of evidence-based clinical practice guidelines.

ACP’s Medical Knowledge Self-Assessment Program (MKSAP) gives internal medicine physicians an opportunity to test their knowledge and compare their results with national averages. In addition, ACP offers postgraduate board review courses, recertification courses, and chapter/regional meetings. For future internal medicine physicians, ACP provides education and career information, produces, and administers an In-Training Examination for residents.

ACP's Practice Support area, offers practice-support tools to enhance the efficiency, quality, and delivery of care, including a Physician & Practice Timeline which helps physicians stay on top of important dates and track deadlines for a variety of regulatory, payment, educational, and delivery system changes and requirements.


ACP is governed by an elected Board of Regents. The Board is advised by a network of ACP committees and by the ACP Board of Governors, which is composed of elected Governors in chapters and regions of the United States. ACP has international chapters in Bangladesh, Brazil, Canada, Caribbean, Central America, Chile, Colombia, India, Japan, Mexico, Saudi Arabia, and Venezuela.
ACP sponsors the Council of Subspecialty Societies, which represents 25 subspecialty societies and internal medicine organizations. ACP is represented in the American Medical Association, the Council of Medical Specialty Societies, and other organizations.

Officer and Staff Spokespersons

2022-23 President Ryan D. Mire, MD, FACP, Nashville, TN
2022-23 Chair, Board of Regents Sue S. Bornstein, MD, FACP, Dallas, TX
President-elect* Omar T. Atiq, MD, FACP, Little Rock, AR
Chair-elect, Board of Regents* Eileen D. Barrett, MD, MACP, Albuquerque, NM
Executive Vice President and CEO Darilyn V. Moyer, MD, FACP, Philadelphia, PA

* to take office as 2023-24 President and Chair, Board of Regents, April 29, 2023.