Radiation-induced brachial plexopathy, especially the chronic and progressive form, has become an increasingly rare entity in patients receiving radiation therapy to the chest wall and axilla. However, for the patients affected by this pathologic process, the chronic pain, decline in function, and absence of a satisfactory treatment are a continuing challenge to the reconstructive peripheral nerve surgeon. The authors have undertaken a review of the relevant literature addressing radiation-induced brachial plexopathy, and here present a summary of the current understanding of the pathophysiology, diagnosis, and treatment of this disorder.