In 2010, alcohol was once again the substance of choice among American youth. In fact, a greater proportion of American young people use alcohol than use other drugs or tobacco, and this use of alcohol by youth under the legal drinking age of 21 has profound negative consequences not just for underage drinkers, but also for their families, their communities, and society as a whole. Despite the modest progress made in recent years, underage drinking remains a serious public health and public safety problem. This Report to Congress, like the Reports before it, summarizes the status of the latest scientific research regarding adolescent alcohol use, describes the characteristics and consequences of underage drinking, and outlines the comprehensive efforts of the Federal Government to address the problem. It also updates and expands the individual state reports, which were first introduced in last year's Report. This year, a survey of all 50 States and the District of Columbia was conducted to collect valuable information about State-supported underage prevention and enforcement activities, programs, and policies. These individual State reports, which were mandated by the STOP Act, provide a valuable resource for Federal, State, and local policy makers, community coalitions, and others interested in addressing underage alcohol use. While the Federal Government has an important role to play in addressing underage drinking, it is clear that we as a country will not succeed without a concerted and informed effort by all of the nation's citizens and at all levels of government. The information provided in this Report can serve as an important tool in that effort. By addressing underage drinking in all of the environments in which youth live--family, school, communities, healthcare systems, and religious institutions--the country can change the way that young people and their parents view underage drinking and create an environment in which underage alcohol use is understood as a serious public health and public safety problem, not a culturally ingrained rite of passage. This Report emphasizes that such change requires a national effort involving parents and other caregivers, educational systems, the public and private sector, concerned individuals and organizations throughout the country, and all levels of government. Appended are: (1) Surveys; (2) Definitions of Variables; (3) State Report Citations; (4) ICCPUD Members; (5) Caffeinated Alcoholic Beverages; (6) DSM-IV-TR Diagnostic Criteria for Alcohol Abuse and Dependence; (7) Abbreviations; and (8) References. (Contains 114 exhibits and 59 footnotes.)