Coronary heart disease (CHD) is the leading cause of mortality in the United States: each year, CHD is newly diagnosed in approximately 1.5 million persons and accounts for an estimated $47 billion in direct and indirect health-care costs (1). Multiple risk factors associated with CHD include genetic susceptibility, elevated serum cholesterol, low levels of high-density lipoprotein cholesterol, cigarette smoking, uncontrolled hypertension, obesity, diabetes mellitus, and physical inactivity (2). This report summarizes information about the potential efficacy and cost-effectiveness of physical activity promotion as a strategy for preventing CHD.