A HALF-CENTURY AFTER THE FEDERAL GOVERNMENT recognized the dangers of tobacco, substantial progress has been made in controlling its use in the United States. The prevalence of smoking has been halved from its peak and the majority of Americans work and live in smoke-free environments. Progress has also been made elsewhere, but in many lowand middleincome countries, prevalence of tobacco use continues to increase. Despite progress, much is unfinished in tobacco control worldwide. Now is a notable moment in tobacco control. The findings on disease causation by active and passive smoking are unassailable, and substantial evidence and experience define best practices for tobacco control. In the United States, the majority of states have some form of smoke-free legislation, and for the first time, Congress has given the US Food and Drug Administration (FDA) authority to regulate tobacco. Most countries have ratified the World Health Organization’s (WHO’s) Framework Convention on Tobacco Control (FCTC), a global public health treaty that obligates ratifying nations to implement comprehensive tobacco control. Moreover, funding for global tobacco control has increased significantly with a $500 million commitment from the Bloomberg Philanthropies and the Bill and Melinda Gates Foundation. Some unfinished business in the United States requires rapid completion. Taxes on cigarettes enhance revenues and benefit public health by increasing cessation and reducing initiation and should be raised further. Despite the recent increase in the federal tax, cigarettes in the United States remain among the most affordable in the world. At least the amount of tax revenues recommended by the Centers for Disease Control and Prevention should be used for tobacco control, and states should not reallocate to other initiatives funds received under the Master Settlement Agreement and originally dedicated to tobacco control. Smokefree public place regulations also need to be extended. The 39 states not mandating completely smoke-free restaurants and bars need to pass comprehensive legislation; there are now abundant models and ample evidence that revenues do not diminish. Smoke-free regulations cannot cover homes, a principal place of exposure for children, and vigorous efforts are needed to make homes smoke-free, including media campaigns and engagement of health care professionals to work with patients and families on this issue. Removing glamorous images of smoking in movies and on television has potential benefits globally, especially for youth and young adults. Smoking cessation is critical for reducing the tragic and predictable burden of disease caused by smoking. Despite decades of research and experience, long-term success rates using available smoking cessation therapies remain around 10%. While available therapies are cost-effective and benefit public health, they remain mostly uncovered by insurance, are as costly as cigarettes, and are not sold accessibly or in convenient and affordably sized units. Enhanced financial support for smoking cessation is needed, along with its full integration into the health care system and a continued search for better cessation methods. One transformative change in domestic business is the Family Smoking Prevention and Tobacco Control Act, federal legislation that was recently signed into law giving the FDA authority to regulate the tobacco industry and its products. The act’s provisions include strengthening advertising restrictions, requiring new and more prominent warning labels, compelling companies to disclose all ingredients in tobacco products, and authorizing the FDA to restrict harmful additives and monitor and reduce nicotine yields. There are potential complexities involved in implementing the act, including developing protocols for assessing the toxicity and addictive potential of tobacco products. Markers of tobacco toxicity can be measured in blood and other biological materials, and WHO has proposed a suite of markers of exposure as well as regulation of levels of tobaccospecific nitrosamines. However, the selected markers, although representative of toxins in tobacco smoke, lack prospective validation for predicting disease. While the mechanisms by which tobacco smoking causes disease have been extensively studied, the resulting evidence is incomplete as to how overall disease risks depend on specific components of tobacco or tobacco smoke. The FDA will be chal-