Joint use of public school facilities is a complex but manageable approach to efficiently enhancing the services and programs available to students and supporting the community use of public schools. Building upon on our 2010 paper titled "Joint Use of Public Schools: A Framework for a New Social Contract," this paper identifies the policy framework needed to support sustainable joint use of public schools. Our goal with this paper is to provide local and state leaders with the policy framework needed to enable and support community use. The policy framework addresses the challenges to harnessing the opportunities and benefits of the community use of K-12 public schools. We discuss the policy elements that have been and can be used to incorporate joint use into normal planning and operations of school districts and local and regional public agencies and to do so in a sustainable and fiscally-responsible manner. The framework addresses policy at the state and local levels and acknowledges that joint use requires public and private agencies to work together in new ways. This paper also describes the need for public transparency and understanding of the full cost of ownership of public school facilities as a critical part of policy. Contains a list of resources developed for school-district practitioners and policymakers. [This paper was written in collaboration with Active Living Research and the Convergence Partnership.]