Symptomatic instability of the sternoclavicular (SC) joint is an uncommon problem. The majority of patients respond well to nonoperative measures, although a small number require reconstructive surgery for symptomatic instability, with varying surgical techniques reported in the literature. We report a series of 5 operations (in 4 patients) with chronic SC joint instability treated by reconstruction of SC and costoclavicular ligaments using an artificial ligament weave (LARS: Ligament Augmentation and Reconstruction System). Preoperative and postoperative disabilities of the Arm, Shoulder, and Hand (DASH) Scores and Oxford Shoulder Scores were collected to evaluate the outcomes. The patients had a mean age of 20 years (range, 17 to 22 y), with 2 male and 2 female patients. Three of the patients had traumatic dislocation of the SCJ and 1 patient had bilateral symptomatic atraumatic instability. Anterior instability was observed in 4 joints and posterior instability in 1 joint. In all cases, reconstruction was achieved with a 30 mm LARS ligament. Postoperative follow-up was for an average of 29 months (range, 19 to 41 mo). The DASH Score improved from 51.7 points (range, 24.2 to 75.0) preoperatively to 13.7 points (range, 8.3 to 20.8) postoperatively. The Oxford Shoulder Scores improved from 20.6 preoperatively (range, 15 to 32) to 41.8 postoperatively (range, 39 to 47). All patients returned to full activity including competitive sports. In conclusion, stabilization of the SC joint using a LARS ligament with a weave technique is a feasible option for young, active patients with symptomatic SC joint instability after failure of nonoperative treatment.