The aim is to specify the genetic causes of dominantly and recessively inherited axonal forms of Charcot-Marie-Tooth disease (CMT) and review the biological basis for these disorders.More than 10 genes that cause axonal CMT have been identified over the past decade. Many of these genes express proteins that are ubiquitously expressed. Clinical phenotypes of many of these disorders are being studied and animal and cellular models of these neuropathies have been created.Identification of these new genetic causes of axonal neuropathy has not only been important for patients and their families but it has also provided exciting new information about disease mechanisms involved in neuronal degeneration. These mechanisms extend beyond the field of axonal CMT and have relevance to sensory neuropathies and motor neuron disorders. Therapeutic strategies for some of these are also provided. We hope that this review will be of interest to clinicians and scientists interested in axonal forms of CMT.