Information was collected for a large number of coronary risk factors on a series of 568 married, white men, aged 30--70 years, who died from coronary heart disease. Information on the same risk factors was collected on an equal number of living controls matched on age, sex, marital status and neighborhood. For regular aspirin users (i.e. greater than or equal to 4 days per week) compared with non-users, the crude matched pair risk ratio estimate was 1.0 (95% confidence limits 0.9--1.1). Even after controlling for possible confounding effects of other variables using a paired multiple logistic regression analysis, there was no evidence of association. These data provide no evidence for a preventive role of regular aspirin intake in coronary deaths.