Immunoneuropathies constitute but a small percentage of polyneuropathies, compared to metabolic or toxic neuropathies. However, refined techniques of immunochemistry and biopsy have increasingly improved the etiological characterisation of immunoneuropathies. This review deals with the present diagnostic tools for investigation of polyneuropathies in general and with special immunological means of diagnosis. After two short case reports from our department, the main groups of peripheral nerve diseases, in which immunologic pathomechanisms are postulated, are described regarding symptomatology, special diagnostics and therapy. These groups of diseases are listed with respect to scientific evidence of their immunologic etiology, ranging from acute and chronic Guillain-Barré-Syndrome to paraneoplastic and neuropathies in HIV infections. The conclusion gives a summary of general pathogenetic considerations in immunoneuropathies.