William J. Marks is Associate Professor of Neurology at the University of California, San Francisco; Medical Director of the UCSF Center for the Surgical Treatment of Movement Disorders; and Director of the Parkinson’s Disease Research, Education, and Clinical Center at the San Francisco Veterans Affairs Medical Center. A graduate of the Johns Hopkins University School of Medicine, Dr. Marks completed residency and fellowship training at the University of California, San Francisco. His clinical and scholarly interests include the medical and surgical treatment of movement disorders, the neurophysiology of neurological disease, and neuromodulation strategies for the treatment of neurological disorders. Dr. Marks’ current investigations include a large-scale prospective, randomized study of subthalamic and pallidal deep brain stimulation for Parkinson’s disease and phase I and II studies of neurotrophic factor gene transfer to treat Parkinson’s disease. In collaboration with neurologists Gail A. Kang, M.D. and Graham A. Glass, M.D., Dr. Marks is also investigating the application of magnetic-resonance based neuroimaging techniques for the diagnosis and characterization of Parkinson’s disease and related disorders.