Mark Hallett is chief of the Medical Neurology Branch and of its Human Motor Control Section at the National Institute of Neurological Disorders and Stroke (NINDS) in Bethesda, Maryland. His research focuses on the physiology of human movement and its pathophysiology in movement disorders such as Parkinson’s disease and dystonia. A cum laude graduate of Harvard College, where he was elected to Phi Beta Kappa, Dr. Hallett received his M.D. cum laude from the Harvard Medical School in 1969. After interning at Peter Bent Brigham Hospital in Boston, he joined the staff of the National Institute of Mental Health’s Laboratory of Neurobiology. He took a residency in neurology at the Massachusetts General Hospital and then conducted research at the Institute of Psychiatry in London on a Mosely Traveling Fellowship. In 1976, Dr. Hallett was appointed director of the Neurophysiology Laboratories at the Brigham, a post he held for eight years while also serving on the faculty of the Harvard Medical School, where he became an associate professor of neurology before accepting his present position at the NINDS. He currently serves as clinical professor of neurology at the Uniformed Services University for Health Sciences in Bethesda. A fellow and former vice president of the American Academy of Neurology (AAN) and an elected member of the American Neurological Association, he is an honorary member of the Australian Movement Disorder Society, the Australian Association of Neurologists, the German Society for Clinical Neurophysiology, the German Neurological Society, the Sociedad Latinoamericana de Movimientos Anormales, the Schweizerische Gesellschaft für Klinische Neurophysiologie, and the Société Française de Neurologie. Dr. Hallett has served as a director and president of the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) and as president of the Movement Disorder Society (MDS) and the International Medical Society of Motor Disturbances. Among his many awards are the United Sates Public Health Service’s Distinguished Service Medal, the 1999 Physician Researcher of the Year Award given by the Physicians Professional Advisory Committee to the Surgeon General, the Director’s Award of the National Institutes of Health (NIH), the AANEM’s Distinguished Researcher Award, the Dino Garavoglia Prize of the Italian Association for Neurological Research, the Pierre Gloor Award of the American Clinical Neurophysiology Society, the NIH’s Outstanding Mentor Award, the first President’s Distinguished Service Award of the of the MDS, the Movement Disorder Research Award of the AAN, and the AAN’s President’s Award. Dr. Hallett is currently editor-in-chief of Clinical Neurophysiology, associate editor of Brain, and a member of the editorial boards of more than a dozen other professional journals. He is the author or co-author of more than five hundred scientific papers and the editor or co-editor of twenty books, including, most recently, (with C. Robert Cloninger, Stanley Fahn, Joseph J. Jankovic, and Anthony E. Lang) Psychogenic Movement Disorders: Neurology and Neuropsychiatry (2005) and (with Giorgio Cruccu) Brainstem Function and Disfunction, which was published by Elsevier last year.