We compared two treatments for tears of the rotator cuff of 1 to 4 cm in size. One group of 22 patients had an arthroscopic subacromial decompression and rotator-cuff debridement; the other comparable group of 23 patients had open repair and acromioplasty. Review was at 2 to 5 years postoperatively. Both groups had similar pain relief and range of active forward flexion, with significant improvement from the preoperative condition. The open repair group scored better for function, strength and overall score, but patient satisfaction was similar in the two groups. We recommend the use of arthroscopic subacromial decompression and debridement for low-demand patients who require mainly pain relief and range of movement. Open repair is necessary if strength and functional recovery are the prime objectives.