Over the past half-century, a substantial body of evidence has accumulated regarding the relationship between physical activity and successful aging. Many chronic diseases and conditions share common preventable causes that are lifestyle related. The World Health Organization has identified regular physical activity as an effective means by which an individual can reduce the risk of developing chronic diseases and conditions and thereby promote independence and aging successfully. Epidemiological research has consistently shown significant decreases in the relative risk of cardiovascular and all-cause mortality among persons who are classified as highly active compared to those in a similar age range who are classified as moderately active or less active. This chapter provides a summary of evidence linking physical activity and the health and quality of life of older persons. A synopsis is provided of current U.S. Federal guidelines regarding the frequency, intensity, duration, and type of physical activity recommended for older adults. Finally, we discuss the role that geriatricians and gerontologists can play in helping older adults to learn how to "be active in their own way." In this chapter, we address a number of questions and concerns frequently raised by older adults about physical activity.