Background After arthroscopic shoulder stabilization, the loss of motion or delayed recovery of motion remains a clinical problem and may lead to poor patient satisfaction. There remains no consensus regarding the optimal position for postoperative immobilization and it is not known whether the position for shoulder immobilization has an effect on motion and functional recovery. Questions/purposes We asked: (1) Do patients treated with external rotation (ER) bracing after arthroscopic anterior shoulder stabilization reliably regain ROM and shoulder function? And (2) what is the frequency of recurrent instability and brace-related complications associated with the use of ER bracing? Methods Forty consecutive patients with a primary diagnosis of anterior shoulder instability underwent arthroscopic stabilization and received postoperative ER bracing; 33 patients (83%; mean age, 23 years; range, 13-44 years) were followed for at least 1 year postoperatively and seven patients were lost to followup. Shoulder ROM and functional scores were recorded preoperatively and at 2 weeks, 12 weeks, 6 months, and greater than 1 year (mean, 16 months) after surgery. Results All patients recovered their preoperative ROM and most patients achieved normal ROM by 3 months after surgery. Significant improvements in American Shoulder and Elbow Surgeons (ASES) and Western Ontario Shoulder Instability (WOSI) scores were observed at each postoperative time point. The mean (± SD) final scores were 95 ± 9 for the ASES and 87%