NICHOLAS S. HILL, M.D. is Chief of the Division of Pulmonary, Critical Care and Sleep Medicine at Tufts Medical Center in Boston and Professor of Medicine at Tufts University School of Medicine. He received his M.D.from Dartmouth Medical School in 1975. He did his internship and residency in Medicine at Tufts-New England Medical Center. He did a fellowship in Cardiovascular Medicine at the University of Massachusetts Medical Center and in Pulmonary Medicine at Boston University School of Medicine. He is Board Certified in Internal Medicine, Pulmonary Diseases, and Critical Care Medicine. He has done extensive research and writing in the fields of noninvasive ventilation and pulmonary hypertension. He is a Past President of the American Thoracic Society and has received a Distinguished Scholar Award in Critical Care from the Chest Foundation of the American College of Chest Physicians.