This volume marks the first of a new series, Contemporary Geriatric Medicine, joining the ever growing "Contemporary" family. As with the other "Contem porary" volumes, our goal is to assist the reader in maintaining currency in a rapidly changing field. Perhaps no field has shown such major advances in such a short time as geriatrics. Over the last several years, the "demographic impera tive" has become a source of concern for many, including clinicians, scientists, econ omists, and health planners. Our geriatric knowledge base continues to grow, often making it difficult to keep abreast of...