It is well established that preventive care reduces the prevalence of disease and helps people live longer, healthier lives. Analysis of the cost-effectiveness of preventive care can guide policy-makers to allocate scarce resources. This synthesis reviews the evidence on the cost-effectiveness of clinical preventive care. Key findings include: although many preventive services are a good value (defined as costing less than $50,000 to $100,000 per Quality Adjusted Life Year), only a few, such as childhood immunizations and counseling adults on the use of low-dose aspirin are widely regarded as cost-saving. Costs to reduce risk factors, screening costs, and the cost of treatment when disease is found can offset any savings from preventive care. Prevention can reduce the incidence of disease, but savings may be partially offset by health care costs associated with increased longevity. Whether these additional competing risk costs outweigh the savings from avoiding the targeted disease depends on how healthy people are during the added life years. Given that so few preventive services save money and that these services are already in wide use, it is unlikely that prevention can reduce health care spending. The authors question whether the emphasis on savings is appropriate and suggest it is better to focus on high value preventive care, taking into account increased longevity and quality of life.