This paper reviews the design and results of published randomized coronary angiographic trials and estimates treatment effect sizes for these trials to clearly demonstrate that antiatherosclerosis interventions are effective in inhibiting the progression of coronary artery disease (CAD). Furthermore, these interventions show differential treatment benefit on particular lesion populations defined by initial lesion severity. The efficacy of such interventions have been virtually unstudied in diabetic populations. Ancillary analyses of these trials implicate certain risk factors for the continued progression of CAD assessed by coronary angiography; although standard lipids such as total cholesterol and LDL-cholesterol are important risk factors, recent evidence suggests that triglycride-rich lipoproteins are also important contributors to progression of CAD, both in treated and untreated trial subjects. Recent reports demonstrating an association between progression of coronary disease assessed by coronary angiography and the risk of clinical events provide critical validation for the use of serial coronary angiography as a surrogate endpoint measure in controlled clinical trials. Finally, the advent of noninvasive ultrasonographic measures of carotid intima-media thickness may provide an important avenue for future testing of antiatherosclerosis interventions.