Diabetic autonomic neuropathy is the most common and troublesome complication of diabetes mellitus. Although involvement of the autonomic nervous system is generally diffuse, symptoms may be confined to a single target organ or organ system. Complications of diabetic autonomic neuropathy contribute greatly to the morbidity, mortality, and reduced quality of life of the person with diabetes and are the major source of increased costs of caring for the diabetic patient. Factors in the pathogenesis of these complications are altered metabolism, vascular insufficiency, loss of growth factor trophism, and autoimmune destruction of nerves in a visceral and cutaneous distribution. The clinical manifestations and the complications of diabetic autonomic neuropathy are reviewed. Future therapeutic strategies that are developed from a better understanding of the pathogenetic processes underlying this disorder can be directed at the cause rather than the manifestations. There are studies in progress that suggest that autonomic nerves can be induced to regenerate, and the future for patients with diabetic autonomic neuropathy is brighter.