David W. Dempster, PhD, is Professor of Clinical Pathology at Columbia University in New York, New York, and Director of the Regional Bone Center at the Helen Hayes Hospital in West Haverstraw, New York. Dr. Dempster obtained his PhD from the University of Glasgow in Scotland and completed postdoctoral studies in Switzerland and France. Several of Dr. Dempster's images of bone structure are permanently displayed at the Smithsonian Institution in Washington, DC. Dr. Dempster is a founding member of the International Society of Musculoskeletal and Neuronal Interactions. He is a Past President of the International Society of Bone Morphometry and a member of the Scientific Advisory Council of the National Osteoporosis Foundation. In addition, Dr. Dempster is a Fellow of the Royal Microscopical Society and an active member of the American Society for Bone and Mineral Research and the Endocrine Society. Dr. Dempster is an Associate Editor of Osteoporosis International, and he has served on the editorial boards of Endocrinology and the Journal of Bone and Mineral Research. He is currently a member of the editorial boards of Bone and the Journal of Clinical Densitometry. His research studies have been continuously supported by the National Institutes of Health for the past 20 years. Dr. Dempster has published over 150 research papers on the pathophysiology and treatment of bone disease.