Schools are thoroughly social settings—both within and beyond the classroom. Yet too many students with autism, intellectual disability, and other developmental disabilities miss out on opportunities to develop the friendships and other supportive relationships that can help them flourish in their learning and life. The Peer to Peer program is a practical, schoolwide approach for supporting inclusion across school activities and fostering peer relationships among students with and without disabilities. Implemented in more than 700 elementary and secondary schools in Michigan—and involving more than 3,000 students with disabilities and more than 14,000 peers—these flexible and feasible programs provide a pathway for schools to expand inclusive experiences for all students. The purpose of this article is to highlight the core components of this schoolwide program and the ways in which it can promote a school climate that is supportive of inclusion.