Diabetic peripheral neuropathies are a group of heterogeneous syndromes with considerable morbidity. At least 50% of diabetic patients develop one or several of these neuropathies within 25 years after the diagnosis. In recent years several pathogenetic mechanisms have been proposed, with the newest findings suggesting a link between several of these hypotheses. The hypoxic hypothesis has revived the role of vascular factors in the pathogenesis of diabetic peripheral neuropathies. Although the exact role of hyperglycemia in the development of peripheral neuropathy is not known, the balance of evidence indicates that attainment and maintenance of normal blood glucose remains the cornerstone of treatment of diabetes and diabetic neuropathies. There is no convincing evidence that any of the treatments devised to correct the metabolic derangements in nerve are of sufficient value or safety to be recommended for routine use.