To more efficiently reduce the risk of coronary heart disease with lipid lowering therapy, cost effectiveness analysis offers an important tool to best determine how to allocate inherently limited resources to improve the health of both individuals and society. Formal economic analysis of the most recent clinical trials with the 3-hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) suggest that secondary prevention of coronary heart disease is very cost effective compared to existing treatment and prevention strategies. Primary prevention is also cost effective but has a much wider range of cost effectiveness depending on an individual baseline risk. Cost effectiveness can be better maximized in primary prevention by treating patients at the highest absolute risk of coronary heart disease. The debate about lipid lowering therapy will now shift from that of efficacy and safety, to that of cost and cost effectiveness. Defining the optimal treatment thresholds for intervention in primary prevention will become a major focus of investigation.