With a view to study the association between smoking and coronary arterial disease, and to identify any quantitative relationship, we undertook a cross sectional analysis of 1105 consecutive male patients investigated by selective coronary arteriography to confirm or exclude coronary arterial disease. Pattern and distribution of disease were evaluated in 3 groups of patients who never smoked; who smoked less than 5 cigarettes per day; and who smoked 6 to 60 or more cigarettes per day. Suitable statistical tests, including adjusting for confounders, were carried out. The prevalence of disease was higher amongst smokers even after adjustment for confounders. The number of cigarettes smoked, and whether the smokers had quit, made no difference to the angiographic appearance or extent of disease. There was no difference in the distribution and severity of disease amongst smokers and non-smokers. Rate ratio of disease amongst smokers in India was higher in those patients between 26 and 45 years of age than in other age groups. Smoking could be identified as a risk marker/risk factor that accelerated the disease process in those prone to develop the disease. It may be advantageous to initiate public health and preventive measures directed specifically at the group aged between 26 to 45 years, and later to address all others who smoke.