Many youth are at risk for failure in school due to various school, family, and community characteristics. To provide more support for youth at risk, school-based mentoring programs have become increasingly popular. However, this seemingly simple intervention is actually quite complex and must be implemented with integrity and fidelity. Although still in emergent stages, key foundational components have been suggested by research to increase the chances of positive outcomes for students. This article discusses the process of building an effective, sustainable mentoring program. Information on specific tools available for program developers and administrators is provided. (Contains 2 tables.)