The late 1980s to mid-1990s period solidified the integration of nationwide adolescent risk-behavior surveillance into prevention design, with the Youth Risk Behavior Survey becoming a stable, credible source for tracking trends and informing policy. Early intervention programs for high-risk youths yielded immediate and short-term reductions in escalation of problem behaviors, shaping school- and community-based prevention initiatives. The theoretical landscape expanded to connect conventionality/unconventionality with health-risk behaviors, providing more nuanced targets for intervention and prevention planning. Historical Significance: These developments established the field's emphasis on data-informed prevention, standardized measurement, and culturally relevant, skills-based interventions for diverse youth populations; their legacy endures in ongoing surveillance systems, evidence-based program design, and nuanced understanding of how social conformity dynamics influence risk behaviors in adolescence.