The Sustainability Guide is intended to provide National Fund leaders and partners with a framework for thinking about what they must do to sustain their work. To create this guide, the authors conducted interviews with site directors and partners of collaboratives that have operated four or more years. They also drew on lessons and resources derived from a W.K. Kellogg Foundation-funded sustainability initiative supporting 11 National Fund regional collaboratives operating in the southern United States. Using these experiences, the authors have developed a framework and gathered dozens of resources and examples to provide insight into the elements of sustainability.