 Subacromial impingement syndrome SAIS is the most frequent cause of shoulder pain. A variety of non-surgical treatments have been advocated to correct the impairments associated with SAIS. Clinical trials support the use of therapeutic exercise and joint mobilizations to improve pain and functional disability associated with SAIS. However, not all patients in these trials had a favorable outcome. Moreover, the effect sizes in these trials were small to moderate. Thus the purposes of this study are to 1. determine the effect of a multi-modal rehabilitation program consisting of strengthening, stretching, manual therapy to the shoulder and spine, patient education, posture, and functional re-training; and 2. identify those patients who are and who are not likely to respond to rehabilitation at the start of care. 