This book provides comprehensive coverage of small fiber neuropathy (SFN), from diagnosis to therapy. It focuses on nerve degeneration and neuropathic pain, and their underlying pathology, physiology, psychophysics, genetics and imaging. In particular, this book describes and discusses the major advances in diagnostic techniques for assessing SFN. These include skin biopsy, evoked potentials, quantitative sensory testing and functional studies, as biomarkers of SFN.SFN is a common peripheral nerve disorder, but was often overlooked due to a lack of objective and specific diagnostic tests for the assessment of small nerve fibers. These fibers mediate thermal sensation, pain detection (nociception), and autonomic regulation. Major symptoms of SFN include neuropathic pain, impaired sensation and autonomic dysfunction. Neuropathic pain poses a diagnostic challenge to clinicians, an essential step for selecting appropriate treatment to relieve suffering.