The results of 50 operative arthroscopies for impingement syndrome were reviewed. Preoperative arthrography was correlated with arthroscopic findings, which were pathologically graded. Results of arthroscopic surgery were assessed. Preoperative arthrography predicted 78% of the complete tears of the rotator cuff and only 25% of the partial tears. Of 40 shoulders followed for at least one year postoperatively, 87.5% had satisfactory results. Arthrography was not as reliable as arthroscopy in predicting partial tears of the rotator cuff. Arthroscopy permitted detailed intraarticular and subacromial visualization and classification of partial and complete tears of the rotator cuff. The early results of arthroscopic acromioplasty and debridement are comparable to those obtained with open operations.