School-based mentoring (SBM) is any intervention that takes place within the school building that connects young people with an adult. In contrast to community-based mentoring, mentor-mentee matches in SBM programs typically meet for shorter periods of time (e.g., one hour per week instead of four hours per week), have a shorter duration, and set more instrumental goals. School-based mentoring programs can support a variety of student outcomes, including grades, attendance, school behavior, and feelings of belonging. In SBM programs, teachers and other school staff members usually identify students who are at risk academically, socially, or emotionally and would benefit from mentoring. This document provides guidance to district staff members or state education agency staff members who want to implement school-based mentoring programs, and outlines: (1) benefits of school-based mentoring; (2) essential structures for successful SBM programs; (3) effective practices for SBM programs; and (4) additional resources.