The future fiscal and economic health of the United States depends on its ability to increase revenues. With high and rising public debt, an aging population that will place increasing demands on federal spending, and a need for new investments in infrastructure, research and development, and human capital, the federal government requires more funding to improve its finances and promote future economic growth and opportunity. Recent fiscal actions that raised current and future budget deficits have made these long-term concerns even more salient. One way to collect more revenue is to reform existing taxes. Instead, or in addition, policymakers could create new revenue sources.