Trends in the prevalence of cigarette smoking and the number of cigarettes smoked per day in Italy were derived from six national probability sample surveys conducted between 1949 and 1983. There was a steady and substantial decrease in reported smoking prevalence among adult men (from 71.4% of current smokers in 1949 to 45.6% in 1983), although the estimated average number of cigarettes smoked per day increased, at least up to 1980. Among women, large increases in smoking prevalence have occurred since the mid-1960s (up to 17.7% among women age 14 or over in 1983) and in average number of cigarettes smoked per day (10.9 in 1980). Both the reported decreasing prevalence among men and the increasing prevalence among women were concentrated mostly in the younger age groups. Data on national surveys of tobacco use may give interesting indications for the analysis of different trends in sex or age groups. They should, however, be interpreted critically, since large discrepancies between interview-based data and information on legal sales of manufactured cigarettes have emerged over the last years, indicating that interview data are largely biased in the sense of systematic underreporting. It seems, therefore, that more than any real changes in smoking habits taking place, it is the attitudes toward reporting smoking that have changed in Italy over the last three decades: in fact, in 1983 cigarette sales reached a maximum both in absolute terms and in average levels per adult.