The Youth Tobacco Survey (YTS) is a surveillance system of self-reported tobacco use knowledge, perceptions and behaviors among Missouri public middle and high school students. The Missouri Department of Health and Senior Services conducts the YTS in coordination with the U.S. Centers for Disease Control and Prevention (CDC) Office on Smoking and Health. State and local tobacco use prevention programs and coalitions use the data to identify emerging trends on which to make programmatic decisions, to establish health objectives and track progress in meeting them, and to inform needed public policy to address identified problems.