With rising job vacancies and a workforce and society that are aging, the United States already has a reservoir of human capital that is not fully tapped: millions of U.S.-born and immigrant college graduates who are in jobs requiring no more than a high school credential or who are unemployed. This human capital, if well-leveraged, could bring important benefits to the U.S. economy, local communities, and the workers themselves. This report offers recommendations for federal and state policymakers and other stakeholders to improve credentialing and other barriers that prevent immigrants and the U.S. born from working at their skill level.