The late 1980s marked the beginning of a sea change in research and intervention on tobacco use by young people, when the first studies were published demonstrating the ease with which adolescents could purchase cigarettes. Since then concern with the commercial availability of tobacco products to youth has grown, becoming deeply entrenched in both research and policy efforts. This paper reviews the history of restrictions on youth access to tobacco, the evidence that commercial sources of tobacco are available and important to adolescents, and the rationale for various components of policies to restrict access. We also review the recent expansion of policies addressing youth access to tobacco at all levels of government, the tobacco industry response to this expansion, and issues that have arisen as this expansion has developed.