At the national level, three surveys conducted using anonymous and confidential self-administered questionnaires provide insights into adolescent smoking. The value of these surveys lies in their representativeness. Unlike sales data and self-reported surveys—which have their limitations—random samples, standardized response conditions, and high response rates ensure data reliability and provide a comprehensive view of the adolescent population, including both smokers and nonsmokers, allowing for the tracking of individual trajectories and the study of factors associated with individuals. [excerpt from presentation]