We compared projections from a dynamic model of US adult smoking prevalence with official estimates of prevalence from the National Health Interview Survey. Ten years after they were made, the model projections closely fit the National Health Interview Survey estimates for 2005 and 2010. We conclude that a verified model of adult smoking prevalence can assist governmental authorities in establishing aspirational but feasible targets for tobacco control. By extension, carefully crafted models can help in goal setting in multiple areas of public health.