A case of postinflammatory aneurysm of the subclavian artery is described. The etiology, pathogenesis, clinical presentation, diagnosis, and therapeutic im plications are discussed and the literature is reviewed. The condition may be quite asymptomatic or present with various local and remote manifestations, including Horner's syndrome. Arteriography usually confirms the diagnosis. Resection of the aneurysm and end-to-end anastomosis of the subclavian artery is recommended whenever feasible, particularly in young patients.