Hereditary sensory and autonomic neuropathies (HSANs) represent a group of heritable peripheral nerve disorders usually taking a severe clinical course. HSAN-affected patients manifest with deep, poorly-healing ulcerations of the feet and hands. To date no definitive cure for HSANs has been developed and the molecular pathology of these disorders is complex. The aim of this review is therefore to present recent findings in terms of HSAN molecular pathogenesis. So far, mutations in 12 genes coding for different proteins have been reported in association with HSAN and the molecular pathogenesis has been elucidated in HSAN1a, HSAN4 and HSAN5. The genes involved in molecular pathogenesis of HSAN code for a wide spectrum of proteins from enzymes to specific nerve growth factors. As far as HSAN1a is concerned, the enhanced understanding has given rise to achievements in experimental therapy particularly in respect to disease models. Despite a rapid progress in studies on the molecular background of HSAN, numerous loci and genes remain still to be discovered.