The authors review the most important contributions of Pierre Marie to the elucidation and description of several neurological diseases, such as Charcot-Marie-Tooth's disease and hereditary cerebellar ataxia, as well as his contributions to Internal Medicine, including his pioneering studies on acromegaly, ankylosing spondylitis, and hypertrophic pulmonary osteoarthropathy. His works led to incontestable advances in the medical sciences that transcended his time.