This interdisciplinary handbook is the first to provide an overview of research and theory about formal and informal adult learning. Jan Sinnott and a team of experts from different fields analyze and synthesize the state of the art today--how mature and aging adults learn and what their motivations are. This major reference examines important theories and models, learning in specific life contexts, the influence of aging on learning, and the future of adult lifespan learning. Extensive reference materials have been developed for students, teachers, policymakers, and practitioners to use in the fields of gerontology, psychology, education, and counseling.