Cigarette smoking is strongly associated with later lung cancer; British data show a 0.83 correlation between tobacco consumption and lung cancer mortality 21 years later. We apply a simple tobacco-consumption model to data from countries in the Organization for Economic Cooperation and Development (OECD) to test the model in some nations and to roughly estimate future rates in others. This analysis provides some indication of the usefulness of the model, which could be applied to predictions for countries in which data are limited. This model predicts a US decline in male lung cancer mortality of approximately 25% by 2005 (a plausible prediction given recent declines in birth-cohort-specific lung cancer mortality rates); it also predicts reasonably well the start of documented declines in lung cancer mortality. According to this admittedly simple model, lung cancer mortality rates will increase in most European countries and Japan until 2000, but the twenty-first-century lung cancer epidemic will mostly occur in Asia.