**1. Introduction**

Diabetic neuropathy is a common microvascular complication of diabetes mellitus. Diabetic neuropathy is a major risk factor for non-traumatic amputations and is thought to play a role in the pathogenesis of other late complications of diabetes. The two major forms of diabetic neuropathy include generalized neuropathy and autonomic neuropathy. Genreralized neuropathy, affecting motor and sensory peripheral nerves can be subdivided further into polyneuropathies which affect multiple nerves and focal neuropathies. The most common form of generalized neuropathy is distal symmetrical polyneuropathy. Autonomic neuropathy affects peripheral autonomic nerves. These autonomic nerves innervate most organ systems of the body and the skin. Both distal symmetric polyneuropathy and autonomic neuropathy cause substantial morbidity and are associated with a high risk of mortality. The hypothesized mechanisms of diabetic neuropathy include ischemic effects caused by vascular abnormalities, disruption of neuronal metabolism, axonal transport mechanisms and repair capabilities, glycation of peripheral nervous system connective tissue, and glycation of Schwann cells or extracellular matrix. In this chapter, we discuss the diagnostic criteria, pathophysiology, epidemiology, and treatment of peripheral and autonomic neuropathy in type 1 diabetes.
