Jules Dejerine (1849–1917) was a French neurologist who contributed to the description of numerous neurologic conditions ranging from neurovascular pathology to neuromuscular disorders. A considerable body of his research was devoted to the peripheral nervous system. In this area, the eponymous Dejerine-Sottas syndrome refers to a form of infantile hereditary neuropathy. Dejerine also contributed to the description of many other disorders of the peripheral nervous system and was even a precursor in the study of acquired neuropathies (as well as acute inflammatory neuropathies, before the first description of the Guillain-Barré syndrome) and in the field of radicular pathology. In this centennial year of his death, we emphasize the variety and originality of Dejerine’s opus on diseases of the peripheral nervous system.