The findings in this report are subject to at least six limitations. First, smoking prevalence might be underestimated because BRFSS does not survey persons in households without any telephone service (2.5%) or with wireless-only telephones (17.5%), and adults with wireless-only service are more likely (30.2%) than the rest of the U.S. population to be current smokers.7 Second, estimates for cigarette smoking are based on self-report and are not validated by biochemical tests. However, self-reported data on current smoking status have high validity.8 Third, the median response rate was 59.1% (range: 32.5%-76.7%) in 1998 and 50.6% (range: 26.8%-65.4%) in 2007. Lower response rates increase the potential for response bias, which could have affected the assessment of trends over time; however, BRFSS aggregated state estimates previously have been shown to be comparable to smoking estimates from other surveys with higher response rates.8 The 2007 median smoking rate of 19.8% reported in this analysis is the same as the national estimate of cigarette smoking reported from the 2007 National Health Interview Survey (19.8%).2 Fourth, trend analyses for Guam and USVI could not be reported because data were not available for the full time span. Fifth, modeling was limited to linear and quadratic trends. However, examination of plots of predicted versus observed prevalence estimates showed that the models fit the data well for the majority of states. For some states, prevalence estimates indicate declines in smoking prevalence might have leveled off since 2005; future trend modeling might need to account for this emerging pattern. Finally, only trends in overall current cigarette smoking prevalence were examined; trends might vary among demographic subpopulations within a state. For example, national trends in current smoking prevalence have varied between non-Hispanic white and black women; cigarette use among these two populations was comparable in the mid-1990s, but use declined more rapidly among non-Hispanic black women than non-Hispanic white women during 2000 and 2001.9 Assessing trends among subgroups is important for targeting interventions to those most at risk.