American College of Physicians

The American College of Physicians (ACP) is a Philadelphia-based national organization of internal medicine physicians, who specialize in the diagnosis, treatment, and care of adults. With 162,000 members, ACP is the largest medical-specialty organization and second-largest physician group in the United States. The ACP is one of two professional organizations representing internal medicine physicians in the United States, and the other organization is the American College of Osteopathic Internists. Its flagship journal, the Annals of Internal Medicine, is among the most widely cited peer-reviewed medical journals in the world.