LA WRENCE G. RAISZ, MD Division of Endocrinology and Metabolism, University of Connecticut Health Center. Farmington. CT The rapid transfer of new knowledge concerning the pathogenesis, diagnosis, preven tion, and treatment of disease into clinical practice has always been a major challenge in medicine. This challenge is particularly difficult to meet in osteoporosis, not only because has been so much new knowledge generated in recent years, but also because this there disorder has not caught the attention of many practicing physicians. The goal of this volume is to help primary care physicians develop a better understanding of osteoporosis and a more effective approach to diagnosis, prevention, and treatment. As primary care physicians become more and more responsible for the maintenance of health and the prevention of disease, osteoporosis must become one of their important concerns. The magnitude of the problem of osteoporosis has been widely publicized. Within the next 30 years, the cost of hip fractures alone is expected to exceed $40 billion a year in the United States and will be a major cause ofincreased mortality. In addition, vertebral crush fractures will cripple more and more of our elderly population, both men and women. This enormous toll is not inevitable. Current methods of identifying individuals at risk and applying preventive programs could reduce the incidence offractures by 50% or more. This should be the minimum goal of clinicians.