The search for nongenetic ways to increase lifespan while maintaining good health and function in old age continues in this prospective cohort investigation of men in the Physicians' Health Study. Yates and colleagues examined whether favorable health and lifestyle factors in early elderly years are associated with subsequent longevity and good function in late life. Among 970 men who lived to 90 years or older, the authors found that regular vigorous exercise and the absence of smoking, overweight, diabetes, and hypertension were associated with exceptional lifespan. In addition, exercise was associated with better late-life physical function, while overweight and history of smoking were associated with worse function. Smoking also was associated with significant decrements in late-life mental function. Men with exceptional longevity had lower incidence of age-associated diseases, later onset of disease, and better late-life function in domains of physical, mental, and self-rated health than did men with shorter lifespan.