In this book we have tried to bring together basic information which has a bearing on how people adapt to growing old. We feel that no single discipline, whether it be psychiatry, sociology, biology, or economics, can claim to offer a comprehensive explanation of how aged people act, think, and feel, or what the multiple determinants of their behavior are. Moreover, we feel that a mere collection of unrelated essays by experts from differing fields is not satisfactory, but that instead an integration of the diverse contributions is needed. -- Preface.