A flu pandemic is a worldwide epidemic of an influenza virus. As such, the United States response to a flu pandemic would have both international and domestic components. Additionally, the domestic response effort would include contributions from every governmental level (local, state, tribal, and federal), non-governmental organizations, and the private sector. This report will focus largely on the role of the Department of Defense (DOD) in supporting the nations domestic response effort, although it will also touch on DODs international role.