Until recently, biogerontology was a backwater of biology, but progress in the qualitative and quantitative genetic analysis of longevity has led to a revolution in aging research. This research has revealed that extended longevity is frequently associated with enhanced metabolic capacity and response to stress. Moreover, it suggests that there are multiple mechanisms of aging. Because of its complexity, the aging process takes us into the realm of integrative biology, and thus, biogerontology should prove instrumental in deciphering the functional and regulatory circuitry of the sequenced genome.