The American Cancer Society's Great American Smokeout is an annual event encouraging smokers to quit. On November 17, 2016, it marked the 41st edition. Since the Surgeon General's first report on smoking and health in 1964, adult smoking rates in the U.S. have dropped by about half, but over 20 million people have died from smoking-related causes. About two-thirds of adult smokers want to quit, but only half made a quit attempt in the previous year. In 2015, 15.1% of U.S. adults were current smokers, about 36.5 million people. Effective help through counseling and medications can triple the chances of quitting. The 2015 National Health Interview Survey (NHIS) showed that the proportion of U.S. adults who smoked cigarettes declined from 20.9% in 2005 to 15.1% in 2015. However, disparities in smoking prevalence persist. Smoking was more common among males, younger adults, American Indian/Alaska Natives, those with lower education, those living below the poverty level, those in the Midwest, those insured through Medicaid or uninsured, those with disabilities, and those with serious psychological distress. Smoking prevalence was highest among American Indian/Alaska Natives (21.9%) and lowest among non-Hispanic Asians (7.0%). Smoking was also more common among those with a GED (34.1%) and those living below the poverty level (26.1%). Despite declines in smoking prevalence, the number of daily smokers decreased from 36.5 million to 27.6 million, while the number of smokers who smoked on some days increased. The mean number of cigarettes smoked per day among daily smokers declined from 16.7 to 14.2. However, the mean number of cigarettes smoked per day did not change significantly between 2014 and 2015. Smoking prevalence was higher among those with serious psychological distress (40.6%) than those without (14.0%). Proven population-based interventions, including tobacco price increases, comprehensive smoke-free laws, anti-tobacco mass media campaigns, and barrier-free access to tobacco cessation counseling and medications, are critical to reducing cigarette smoking and smoking-related disease and death among U.S. adults, particularly among subpopulations with the highest smoking prevalence. Efforts to address disparities in smoking are crucial to further reducing smoking prevalence in the United States.The American Cancer Society's Great American Smokeout is an annual event encouraging smokers to quit. On November 17, 2016, it marked the 41st edition. Since the Surgeon General's first report on smoking and health in 1964, adult smoking rates in the U.S. have dropped by about half, but over 20 million people have died from smoking-related causes. About two-thirds of adult smokers want to quit, but only half made a quit attempt in the previous year. In 2015, 15.1% of U.S. adults were current smokers, about 36.5 million people. Effective help through counseling and medications can triple the chances of quitting. The 2015 National Health Interview Survey (NHIS) showed that the proportion of U.S. adults who smoked cigarettes declined from 20.9% in 2005 to 15.1% in 2015. However, disparities in smoking prevalence persist. Smoking was more common among males, younger adults, American Indian/Alaska Natives, those with lower education, those living below the poverty level, those in the Midwest, those insured through Medicaid or uninsured, those with disabilities, and those with serious psychological distress. Smoking prevalence was highest among American Indian/Alaska Natives (21.9%) and lowest among non-Hispanic Asians (7.0%). Smoking was also more common among those with a GED (34.1%) and those living below the poverty level (26.1%). Despite declines in smoking prevalence, the number of daily smokers decreased from 36.5 million to 27.6 million, while the number of smokers who smoked on some days increased. The mean number of cigarettes smoked per day among daily smokers declined from 16.7 to 14.2. However, the mean number of cigarettes smoked per day did not change significantly between 2014 and 2015. Smoking prevalence was higher among those with serious psychological distress (40.6%) than those without (14.0%). Proven population-based interventions, including tobacco price increases, comprehensive smoke-free laws, anti-tobacco mass media campaigns, and barrier-free access to tobacco cessation counseling and medications, are critical to reducing cigarette smoking and smoking-related disease and death among U.S. adults, particularly among subpopulations with the highest smoking prevalence. Efforts to address disparities in smoking are crucial to further reducing smoking prevalence in the United States.