Smoking causes premature death and disease in children and adults who do not smoke but are exposed to secondhand smoke (SHS). To assess the state-specific prevalence of current smoking among adults in the United States and the proportions of adults who report having smoke-free home rules and smoke-free policies in their workplace, CDC analyzed data from the 2005 Behavioral Risk Factor Surveillance System (BRFSS). This report summarizes the results of that analysis, which indicated a threefold difference (from lowest to highest) in self-reported cigarette smoking prevalence in 50 states, the District of Columbia (DC), Puerto Rico (PR), and the U.S. Virgin Islands (USVI) (range: 8.3%-28.7%). Wide variations also were observed in USVI and the 14 states that assessed prevalence of smoke-free home rules (from 63.6% [Kentucky] to 82.9% [Arizona]) and smoke-free workplace policies (from 54.8% [Nevada] to 85.8% [West Virginia]). Evidence-based, comprehensive tobacco prevention and control programs that focus on decreasing smoking initiation, increasing smoking cessation, and establishing smoke-free workplaces, homes, and other venues should be continued and expanded to reduce smoking prevalence, exposure of nonsmokers to SHS, and smoking-related morbidity and mortality.