Tobacco, alcohol, and cannabis are the most commonly used psychoactive substances among young adults in France. However, it is other drugs that most distinguish them from the rest of the population. Levels of use vary greatly by age and gender, but also by socioeconomic background. The Life Events and Health (EVS) survey, conducted in 2005, sheds new light on the use of legal and illegal psychoactive substances among young adults aged 18–34. It provides a clearer picture of the sociodemographic characteristics of these users and allows for an examination of potential links to violence experienced recently or in the past. Young women consistently consume fewer substances than young men, though this trend is less pronounced for tobacco than for other substances. Overall, illicit drug use appears strongly linked to violence experienced in the two years preceding the EVS survey and to family events experienced during childhood or adolescence, while regular tobacco and alcohol use is more clearly associated with social contexts. Regular alcohol use thus appears linked to a higher level of education, while unemployment is associated with illicit drug use and more frequent daily smoking.[author’s abstract]