Study Design: Descriptive postoperative follow-up research. Objectives: The purpose of this investigation was to describe the return-to-competition rate and functional outcome of overhead athletes following arthroscopic thermal-assisted capsular shrinkage (TACS).Background: Traditional open procedures to correct instability in overhead athletes, such as capsulolabral repairs and capsular shifts, have produced less-than-favorable results, which have led to the development of TACS. Currently there are no long-term follow-up studies documenting the efficacy of this procedure in groups greater than 31 subjects or for a time period greater than 27 months. Methods and Measures: Two hundred thirty-one consecutive overhead athletes who due to symptoms of hyperlaxity had previously undergone a TACS procedure from 1997 to 1999 were selected for inclusion in the study. During a 1-month period, 130 of these athletes (mean age ± SD, 24 ± 6 years; 113 male, 17 female) were contacted by phone for follow-up at a mean of 29.3 months postoperatively (range, 15.4-46.6 months). Of the 130, 105 participated in baseball (80 pitchers), 14 in softball, 4 in football (quarterbacks), 4 in tennis, and 3 in swimming. Fifty-four (42%) subjects were professional, 49 (38%) collegiate, 16 (12%) high school, and 11 (8%) recreational athletes. One hundred twenty-three of the 130 (95%) underwent 1 or more concomitant procedure(s) at the time of TACS. Most commonly performed were labral debridements (69%), rotator cuff debridements (65%), and superior labral repairs (35%). Subjects who returned to competition were retrospectively evaluated using a modified Athletic Shoulder Outcome Rating Scale to subjectively assess pain, strength and endurance, stability, intensity, and performance. Overall results were based on a 90-point scale with scores of 80 to 90 representing excellent, 60 to 79 good, 40 to 59 fair, and less than 40 poor results. Results: One hundred thirteen out of 130 subjects (87%) returned to competition. Mean (±SD) time from surgery to return to competition was 8.4 ± 4.6 months. Mean outcome score for all subjects was 79/90; 75 (66%) subjects had excellent, 24 (21%) good, 11 (10%) fair, and 3 (3%) poor result. The mean outcome score for males was 80/90 and for females was 70/90.