Background: This study examines the extent to which high alcohol consumption, drug use, and delinquency vary between schools with different socioeconomic characteristics, over and above the pupil's own sociodemographic background. Methods: Analyses are based on data on 5484 ninth-grade students distributed over 93 schools in Stockholm, from the 2010 Stockholm School Survey. School-level information was retrieved from the Swedish National Agency for Education. School disadvantage was determined by combining information on the level of education among parents and the share of pupils with a nonnative background, 2 aspects that have been shown to be central to school segregation in Sweden. Results: Results indicate significant school-to-school differences in relation to all outcomes. The risk for high alcohol consumption and drug use is greater in more advantaged school settings, adjusting for individual characteristics, whereas the opposite is true in relation to criminal behavior. The school's level of collective efficacy also seems to play an important, albeit not mediating, role. Conclusions: Regardless of an adolescent's own background, the risk of having adverse health behaviors is higher at certain schools compared to others. However, school socioeconomic factors do not influence health behaviors consistently; instead, it seems as if the association varies depending on the behavior under study.