Peripheral neuropathies constitute a diverse group of diseases caused by a wide range of genetic, toxic, metabolic, and inflammatory insults to the peripheral nervous system. A considerable proportion of neuropathies are believed to have an autoimmune basis, either as a feature of systemic autoimmune diseases, vasculitides, or paraneoplastic or postinfectious syndromes, in association with lymphoproliferative diseases, or as isolated peripheral nerve syndromes. In clinical practice, the cause of sporadic neuropathies is often obscure, resulting in the frequent use of multiple screening tests to aid in diagnosis. Over the last 20 years, there has been a widespread increase in the use of antiganglioside antibody assays as diagnostic tools, based on the recognition from research studies that gangliosides are important autoantigens in many patients with autoimmune peripheral nerve disorders (1).