Results indicated that a positive school climate and a positive sense of community were associated with less adolescent substance use and that a positive sense of community moderated the relation between peer and parental influence on adolescent substance use, acting as a protective factor. Findings suggest that adolescent's views of their school and community not only were associated with the amount of substance use they reported, but the contextual systems might protect these adolescents from the strong influences of negative peer pressure and negative parenting attitudes and behavior. Data were gathered from 14,548 high school students from 19 schools in the Midwest who were surveyed using the Dane County Youth Assessment. Variables included parental factors, peer influence, school climate, and sense of community. Alcohol/marijuana and cigarette use were examined as separate outcomes. Tables, appendix, and references