Claudia I. Henschke, Ph.D., M.D., is chief, Division of Chest Imaging, at the New York Presbyterian Hospital-Cornell Medical Center and professor of radiology at the Weill Medical College of Cornell University. She has served on committees of the National Institutes of Health, the National Academy of Science, the Radiological Society of North America, and the American College of Radiology. For information about her work on early detection of lung cancer, see www.nyelcap.org.