The Afterschool Alliance’s Starting a Program Toolkit is a practical, user-friendly resource designed to help launch or enhance out-of-school time (OST) programs. It offers planning guides, age-specific best practices, curriculum tools, and staffing resources—all grounded in research and aligned with youth development and prevention goals. Prevention professionals will find valuable supports for building programs that foster social-emotional growth, academic enrichment, and community engagement. The toolkit also includes guidance on securing funding, offering meals, and creating inclusive, equitable environments. Whether starting from scratch or improving an existing program, this toolkit provides the foundation to build sustainable, high-quality OST services.