A common protocol was followed for collecting risk factor data and coronary arteries and aortas from approximately 1,000 autopsies per year for three years. Specimens were collected and preserved in a standardized way at each collection center. Data management and statistical analysis were conducted at the University of Texas in San Antonio. The unit at Louisiana State University was composed of three central laboratories: the lipid biochemistry center; the coronary heart disease risk factor center; and a gross morphology center. The morphometry central laboratory was located at Ohio State University. Administration and coordination were directed from the University of Chicago and the University of Illinois.