We reviewed a series of professional and competitive low-handicap golfers with shoulder pain. All but one player (34/35) had pain in the left shoulder. A high incidence of problems (53%) related to the acromioclavicular joint was noted in these golfers with left shoulder pain. With proper treatment all but one (17/18 [94%]) of the golfers with acromioclavicular joint problems was able to return to competitive golf. By studying the mechanics of the golf swing, a possible mechanism for this high incidence of acromioclavicular joint problems is given.