Pilot data from an ongoing case-comparison study of risk factors for coronary and carotid atherosclerosis as defined by angiography and B-mode ultrasound provided a background for this project. Patients from the pilot study were used in this study. Beginning in 1986, traditional risk factors such as lipids, lipoproteins, blood pressure, diabetes, and smoking were measured as were non-traditional risk factors such as apolipoproteins and genetic markers. The cohort was followed for 3.5 to 8.5 years for incidence of clinical events. Multivariate techniques were used to relate disease or risk factor status to all-cause mortality, fatal and non-fatal myocardial infarction, and fatal and non-fatal stroke. The same subjects were re-evaluated periodically by B-mode for extent of carotid atherosclerosis. A fifty percent random sample of patients positive for both cerebrovascular disease and coronary artery disease and a fifty percent random sample of patients negative for both cerebrovascular disease and coronary artery disease had repeat B-mode measurements at 2.5 years. All patients surviving at the end of five years had repeat B-mode scans.