Symptomatic irrepairable rotator cuff tears usually entail complete loss of the substance of the supraspinatus and infraspinatus tendons. Loss of external rotation control and cranial migration of the humeral head on attempted flexion or abduction of the shoulder are the functional hallmarks. Transfer of the latissimus dorsi tendon from the humeral shaft to the superolateral humeral head provides a large, vascularized tendon that can be used to close a massive cuff defect and that exerts an external rotation and head-depressing moment that allow more effective action of the deltoid muscle. This procedure was carried out in 14 patients without any significant complications. Pain relief and functional results in those four cases with a minimum follow-up period of one year (average, 14 months) compared favorably with alternative treatment methods and warrant further anatomic, electromyographic, and clinical investigation.