The Québec Survey on Smoking, Alcohol, Drugs and Gambling in High School Students provides a two-year portrait of the prevalence and evolution of tobacco use (since 1998), the use of legal and illegal psychoactive substances (since 2000) and the involvement in gambling (since 2002) among Québec high school students. This bulletin presents the main findings of the report of the survey’s sixth edition. As with previous editions, stakeholders will find reliable, objective and quality data to support their actions or verify their effectiveness.