To evaluate return to sport, clinical outcomes, and complications in a series of athletes with painful partial-thickness rotator cuff tears treated with the arthroscopic in situ repair with a minimum 2-year follow-up. Retrospective case series. Seventy-two patients who had undergone an arthroscopic in situ repair for partial-thickness rotator cuff tears were evaluated. We assessed return to sport and the level achieved after surgery. Clinical assessment consisted of glenohumeral range of motion measurement and the American Shoulder and Elbow Surgeons score. Pain was recorded using a visual analog scale. Postoperative complications were also assessed. The mean age was 42.2years (range, 21-66years), and the mean follow-up was 54months (range, 24-113months). Sixty-one patients (87%) were able to return to sports. Fifty-six patients (80%) returned to the same level they had previous to the injury. The mean interval between surgery and return to competition was 5.6months. The final functional outcomes were related neither to the type of sports nor to the level of competition before the injury. All active range of motion parameters improved significantly (P < .0001). The American Shoulder and Elbow Surgeons score improved from 43.3 to 88.1, and the visual analog scale scores improved from 6.1 to 1.2 (P < .0001). No significant difference regarding return to sports orfunctional outcomes was found between articular and bursal-sided tears. Only 5 patients developed a postoperative adhesive capsulitis that responded to physical therapy. In patients with partial-thickness rotator cuff tears,arthroscopic in situ repair resulted in excellent functional outcomes, with most of the patients returning to sport andat the same level they had before injury. The results were equally favorable in articular and bursal tears. Level IV, therapeutic case series.