The inheritance of the hereditary motor and sensory neuropathies (HMSN) is usually autosomal dominant. We studied a kinship with a pattern of X-linked dominant inheritance. The phenotype was similar to HMSN of the “intermediate” type. Men were more severely affected than women, and hypertrophic nerves were not found. Nerve conduction was very slow in men, but it was mildly slow or normal in women. No male-to-male transmission was found in six generations.