Thirty-nine reoperations in 38 patients with recurrent symptoms of neurogenic thoracic outlet syndrome were performed by the supraclavicular approach. Scarring around the brachial plexus was the primary cause in 59% of procedure, whereas in 41% of reoperations residual osseous and soft tissue anomalies were identified in the supraclavicular area and were responsible for recurrence of symptoms. Anterior and middle scalenectomy and neurolysis of the brachial plexus were the procedures of choice. Complications included pleural entry (62%), lymphatic leak (10%), brachial plexus and phrenic nerve injuries (5% each), and long thoracic and recurrent laryngeal nerve palsies (3% each). The initial success rate for secondary operations was 74%, and long-term success at 18 months was 45%. Patients who had demonstrable anatomic anomalies had better short- and long-term results than had patients with scarring alone. Compared with the results of primary operations for neurogenic thoracic outlet syndrome, reoperations led to a longer hospital stay and inferior long-term results. Supraclavicular decompression allows maximal exposure of the brachial plexus and identification and correction of causative soft tissue and bony anomalies. For these reasons we recommend this as the approach of choice in both primary and secondary operations for neurogenic thoracic outlet syndrome.