We reviewed the cases of thirty-seven young patients, ten to thirty-six years old, who had had spontaneous atraumatic anterior subluxation of the sternoclavicular joint. Sudden atraumatic subluxation is quite alarming to the patient and the physician. Twenty-nine of the thirty-seven patients were treated non-operatively by observation and rehabilitative measures. Eight patients had been treated elsewhere with attempted operative reconstruction of the sternoclavicular joint or with resection arthroplasty. After an average follow-up of eight years, the twenty-nine patients who were treated non-operatively (group I) had excellent results, with no limitations of activity or changes in life-style. The eight patients who were treated operatively (group II) had numerous problems, including noticeable scars, persistent instability, pain, or limitation of activity that resulted in an alteration in lifestyle. Three of the eight patients had had a resection of the medial portion of the clavicle. Two of them had a second resection and the third patient had a third resection. A thoracic-outlet syndrome developed in this patient and the clavicle had to be totally resected to obtain relief. Since spontaneous atraumatic anterior subluxation of the sternoclavicular joint has a benign natural course, it should not be treated with operative stabilization of the joint. Instead, a conservative approach that includes education and reassurance of the patient will result in an unaltered lifestyle with no limitation of activity and little or no discomfort.