Peripheral neuropathy is a devastating complication of diabetes mellitus because of the debilitating symptoms it causes or associated higher risk of other complications, in particular those involving the lower extremity. This chapter will review the prevalence, incidence, and risk factors for different types of diabetic neuropathy. There are seven major types of diabetic neuropathy: (1) distal symmetric polyneuropathy, (2) autonomic neuropathy, (3) nerve entrapment syndromes, (4) proximal asymmetric mononeuropathy (also known as diabetic amyotrophy), (5) truncal radiculopathy, (6) cranial mononeuropathy, and (7) chronic inflammatory demyelinating polyradiculopathy (CIDP). This chapter will focus mainly on the first two types of neuropathy, but will review the available data on the epidemiology of the other types of neuropathy. Crosssectional or case-control studies conducted in a population-based sample (such as a defined community or health plan enrollment) were considered for this chapter based on review of Medline citations using the keywords “epidemiology,” “diabetes,” and “neuropathy” from 1966 to February 2005 review of bibliographies of the articles obtained from the Medline search for relevant citations, and review of the authors’ files. Clinic-based cross-sectional or case-control studies have not been considered except in the case of rare conditions, for which no other data exists. All prospective studies, and some randomized controlled trials, were considered. Of the five community-based cross-sectional studies reviewed of subjects with type 2 diabetes that presented data on risk factors for neuropathy, three reported a higher prevalence of this outcome with longer diabetes duration and higher glycosylated hemoglobin, and two found neuropathy prevalence correlated with age and height. Only three community-based cross-sectional studies addressed neuropathy prevalence in subjects with type 1 diabetes in association with risk factors.