The author describes 1068 patients with brachial plexus lesions who were referred to him during a period of 18 years. Seventy two percent of the injuries were caused by road traffic accidents. Traction or crush injuries were the usual type encountered. They may occur at five levels above, behind and below the clavicle. Of 329 patients who underwent operation, 23% had an associated injury of a major vessel and 80% had multiple injuries elsewhere. The operative approach preferred is described and the principles governing the choice of nerve repair, nerve graft and nerve transfer are discussed. The details of the problems encountered and the procedures carried out in this group of patients are given, and the results obtained are closely analysed. In about 15% of supraclavicular injuries reconstruction of the plexus is worthwhile. The results in infraclavicular lesions are much better with a high level of success if treated early. Only 5 patients had direct lacerations of nerves of the plexus and another 5 had suffered gunshot wounds. Only 11 out of 80 cases of obstetric palsy seen since 1976 have been operated on. The majority of the patients were seen late. At operation similar lesions were encountered as in adults, and useful improvement was obtained in some cases. In post-irradiation lesions of the plexus good results may be obtained if operation is undertaken early. Otherwise surgery should only be performed to relieve severe pain.