Purpose: This study examines results from a multifaceted social development approach to prevention called Raising Healthy Children (RHC). RHC focuses on enhancing the developmental expression of protective factors and reducing their developmental expression of risk factors to promote positive youth development and prevent adolescent problem behaviors. Participants include 1040 elementary students in first and second grade in 1993 who were enrolled in 10 area schools in the Pacific Northwest and randomly assigned into experimental and control groups. The interventions are guided by the Social Development Model (Catalano & Hawkins, 1996), a theory of the development of both prosocial and antisocial behaviors. RHC interventions address the developmental expression of risk and protective factors through three socializing institutions, the family, school, and peer group. The school interventions provided training for teachers in instructional improvement and classroom coaching designed to increase student's commitment and attachment to school while reducing academic failure. The family interventions provided parenting workshops and home-based services to increase parents' skills in child rearing, to increase attachment and commitment to the family while decreasing family management problems. The peer interventions provided children opportunities to learn and practice social and emotional skills in the classroom and in social situations. Methods: Self report data from parents and students are collected each spring. Additionally, teachers complete behavior checklist for all students annually. HLM, Two part latent growth modeling and logistic regression are used to examine differences between students in the intervention and control conditions. Results: RHC students in intervention schools had significantly higher academic performance and a stronger commitment to school compared to their peers in the control group according to teacher reports after 18 months of intervention. Similarly, teachers rated RHC students to be less involved in antisocial behaviors and have higher social competency than their control peers. Regression results for parent ratings also demonstrated that RHC students had higher academic performance and a stronger commitment to school than control students. A two-part latent growth modeling strategy was employed to examine change in both substance use-vs.-nonuse and frequency-of-substance use outcomes during grades 9 and 10. Results indicated significant intervention effects on growth trajectories for frequency of alcohol and marijuana use, but not for use vs. nonuse. Further, logistic regression analyses conducted during years 10 and 11 to examine the specific effects of safe driving booster sessions, revealed that students in the intervention group were more likely to report having a written driving contract and to have participated in making driving rules in the family than students in the control group. Students in the intervention group reported less driving with someone who has been drinking and driving under the influence of alcohol. Implications for Practice: These findings provide support for social development interventions that target the developmental expression of risk and protective factors. Implications for school social work will be discussed.