Each year in the United States, approximately 440,000 persons die of a cigarette smoking-attributable illness, resulting in 5.6 million years of potential life lost, $75 billion in direct medical costs, and $82 billion in lost productivity. To assess smoking-attributable morbidity, the Roswell Park Cancer Institute, Research Triangle Institute, and CDC analyzed data from three sources: the Behavioral Risk Factor Surveillance System (BRFSS), the National Health and Nutrition Examination Survey III (NHANES III), and the U.S. Census. This report summarizes the results of that analysis, which indicate that an estimated 8.6 million persons in the United States have serious illnesses attributed to smoking; chronic bronchitis and emphysema account for 59% of all smoking-attributable diseases. These findings underscore the need to expand surveillance of the disease burden caused by smoking and to establish comprehensive tobacco-use prevention and cessation efforts to reduce the adverse health impact of smoking.