Cigarette smoking has been identified as the chief avoidable cause of death in the United States. Several estimates of mortality attributable to cigarette smoking have been reported, including 270,000 deaths for 1980 and 314,000 deaths for 1982. Published estimates vary considerably because of changing mortality rates, decreasing smoking rates, and differences in methods used. Smoking-attributable mortality and years of potential life lost (YPLL) for 1984 are analyzed in this report.