Each volume in the Handbooks of Aging series represents one of the three main influences on the Handbook of the Biology of Aging, Handbook of the Psychology of Aging, and Handbook of Aging and the Social Sciences. Each of the Handbooks presents critical comprehensive reviews of research knowledge, theories, concepts, and issues by the foremost scholars in the field. Chapters are selected to portray discrete units of research study, long-standing areas of research, and new developments.