Community-Based Participatory Research (CBPR) has the twin goals of generating data and shaping policy decisions, yet examples that combine these goals are scarce in the literature. We describe how a community-based survey was created and used to help develop a county health plan. The Genesee Health Plan (GHP), a community-initiated non-profit organization, provides primary care, prescription drugs, and specialty care to uninsured, low-income adults through a network of independent physicians, clinics, and hospital systems. As part of an advocacy effort, GHP supporters used results from the Speak to Your Health! Community Survey to gain financial and political support for GHP. Our study, which used CBPR principles, was created by the community, local health department, and university partners. As a result, Genesee County became one of the first counties in the United States to make basic health care available to nearly all of its uninsured, low-income adults.