Coronary artery disease (CAD) is probably the most common example of a multifactorial disease that can be reduced in incidence (if not prevented in some cases) by appropriate attention to and control of risk factors. This conclusion is supported by large epidemiologic studies, confirmed by randomized intervention trials in which a putative risk factor is attacked with specific therapy, and put into context by the results of multiple risk factor intervention trials. The job of the physician is to take the pieces of scientific data regarding CAD and extrapolate them, if appropriate, to individual patients, who presumably with benefit from all the hard work their predecessors in clinical trials went through to prove that the intervention was successful.