Objective: This evaluation study assessed the impact of Be Yourself, an after-school program aimed at decreasing risky sexual behaviors among 9th and 10th grade Latino youth. Methods: A cluster-randomized trial was conducted with 12 schools. Quantitative survey data was collected at baseline and 6 months post-program completion (N = 1356), and implementation and fidelity data was collected continuously throughout the 3-year project period. Results: Only 41.2% intervention youth and 32.7% control youth attended more than 75% of the sessions. No statistically significant differences were found between the intervention and control groups for any risky sexual behavior outcome measures. Conclusions: Although the intention-to-treat analysis did not yield significant impact findings, this 5-year research and demonstration project generated important lessons learned and provided the foundation for future Latino youth-based interventions. [ABSTRACT FROM AUTHOR]