Although cigarette smoking has substantially declined since the release of the 1964 Surgeon General's report on smoking and health,* disparities in tobacco use exist among racial/ethnic populations (1). Moreover, because estimates of U.S. adult cigarette smoking and tobacco use are usually limited to aggregate racial or ethnic population categories (i.e., non-Hispanic whites [whites]; non-Hispanic blacks or African Americans [blacks]; American Indians and Alaska Natives [American Indians/Alaska Natives]; Asians; Native Hawaiians or Pacific Islanders [Native Hawaiians/Pacific Islanders]; and Hispanics/Latinos [Hispanics]), these estimates can mask differences in cigarette smoking prevalence among subgroups of these populations. To assess the prevalence of and changes in cigarette smoking among persons aged ≥18 years in six racial/ethnic populations and 10 select subgroups in the United States,(†) CDC analyzed self-reported data collected during 2002-2005 and 2010-2013 from the National Survey on Drug Use and Health (NSDUH) (2) and compared differences between the two periods. During 2010-2013, the overall prevalence of cigarette smoking among the racial/ethnic populations and subgroups ranged from 38.9% for American Indians/Alaska Natives to 7.6% for both Chinese and Asian Indians. During 2010-2013, although cigarette smoking prevalence was relatively low among Asians overall (10.9%) compared with whites (24.9%), wide within-group differences in smoking prevalence existed among Asian subgroups, from 7.6% among both Chinese and Asian Indians to 20.0% among Koreans. Similarly, among Hispanics, the overall prevalence of current cigarette smoking was 19.9%; however, within Hispanic subgroups, prevalences ranged from 15.6% among Central/South Americans to 28.5% among Puerto Ricans. The overall prevalence of cigarette smoking was higher among men than among women during both 2002-2005 (30.0% men versus 23.9% women) and 2010-2013 (26.4% versus 21.1%) (p<0.05). These findings highlight the importance of disaggregating tobacco use estimates within broad racial/ethnic population categories to better understand and address disparities in tobacco use among U.S. adults.