As not-for-profits increasingly take on big issues, some are turning to “collective impact.” This cross-sector approach involves nonprofits, government, businesses and communities working together to solve a specific problem. Collective impact adherents often cite several requirements for success: a common vision, a shared measurement system, mutually reinforcing activities, continuous communication and a separate support organization. Before joining a project, understand that you may need to provide substantial resources, commit to the long-term and make certain leaps of faith.