A recent development in the evaluation of peripheral neuropathy patients has been the identification of autoantibodies directed against various peripheral nerve antigens. For some conditions, assay for the antibodies can be very helpful in confirming a diagnosis. In others, an antibody may be associated with clinical findings that are neither distinctive nor specific, and the role of the antibody in the pathogenesis of the clinical disease may remain uncertain. The appropriate use of antibody assays in clinical diagnosis and management is therefore often unclear. This article highlights the historical background for the best-described "antinerve" antibodies, and reviews the biochemistry, immunology, pathophysiology, and treatment implications of the associated clinical conditions.