Developing and sustaining comprehensive school mental health systems should be a shared endeavor between schools and community partners; the task should not rest solely on the shoulders of the K-12 education sector. Community partners, including health and behavioral health providers, can augment the continuum of services available to students and families by offering services directly in schools, and by facilitating referral pathways when students need support outside of the school building. Colleges and universities are also critical community partners in building comprehensive school mental health systems. They can foster a robust workforce, offer professional development, provide mental health services, and engage in research and evaluation to study impact and inform quality improvement. This brief describes each of these opportunities for partnership with colleges and universities and highlights strategies and exemplars to help accelerate innovation and advancement in K-12 school mental health systems.