Social environmental assessments can play a critical role in prevention planning in schools. The purpose of this study was to describe the importance of conducting social environmental assessments, demonstrate that complex social environmental data can be simplified into a useful and valid typology, and illustrate how the typology can guide prevention planning in schools. Data collected from 532 3(rd) through 5(th) graders using the Elementary School Success Profile were analyzed in the study. A latent profile analysis based on eight child-report social environmental dimensions identified five patterns of social environmental risk and protection. The classes were labeled High Protection, Moderate Protection, Moderate Protection/Peer Risk, Little Protection/Family Risk, and No Protection//School Risk. Class membership was significantly associated with measures of well-being, social behavior and academic performance. The article illustrates how the typology can be used to guide decisions about who to target in school-based preventions, which features of the social environment to target, and how much change to seek. Information is provided about online resources for selecting prevention strategies once these decisions are made.