Despite the risks, approximately 46.6 million U.S. adults continue to smoke cigarettes. Smoking causes more than 440,000 deaths in the United States each year. The Federal Food, Drug, and Cosmetic Act (FD&C Act) requires FDA to establish and periodically revise a list of Harmful and Potentially Harmful Constituents (HPHCs). In guidance issued in January 2011, FDA has indicated its belief that the phrase ‘harmful and potentially harmful constituent’ includes any chemical or chemical compound in a tobacco product or in tobacco smoke: that is or potentially is inhaled, ingested, or absorbed into the body; and that causes or has the potential to cause direct or indirect harm to users or non-users of tobacco products. In April 2012, FDA established the HPHC list, which contained 93 constituents. Section 904(a)(3) of the FD&C Act requires tobacco product manufacturers to determine HPHC quantities in tobacco products and smoke and report those quantities to FDA beginning on June 22, 2012. Also in April 2012, FDA published a draft guidance document stating that, in order to comply with Section 904(a)(3), FDA does not intend to enforce the statutory requirement to provide quantities of all constituents identified by FDA as HPHCs by June 22, 2012, if manufacturers or importers complete testing and reporting for an abbreviated list of HPHCs. HPHC information can be very valuable to FDA in accomplishing its public health mission including informing tobacco products standards, marketing authorization decisions, and the public of the risks of tobacco use.