Shoulder pain is a common entity in a primary care physician's practice. The unique anatomy of the shoulder allows for almost unrestrained motion in all planes. A thorough history and physical examination are important to ensure efficient patient evaluation. Further assessment may include radiographic and diagnostic laboratory tests. This article presents an organized approach to the anatomy, physiology, and pathology of common shoulder disorders for the primary care physician. The distinction between disorders that are intrinsic or extrinsic to the shoulder joint is discussed. Treatment and the need for appropriate referral are described.