Understanding the pathophysiology and treatment of rotator cuff disorders is the key to understanding all other aspects of shoulder rehabilitation. Impingement rehabilitation focuses on strengthening the humeral head depressors, while ignoring the deltoid and supraspinatus muscles. Later treatment includes specific retraining of scapular balancing muscles. The final phase of treatment includes strengthening the prime humeral movers in positions that avoid further stress to the injured rotator cuff tendons and, last of all, specifically strengthening the supraspinatus muscle.