This report from the CSIS Project on Prosperity and Development looks at the domestic resource mobilization (DRM) reforms in developing countries through a political economy lens. As countries mobilize more resources to fund their governments and services, they can think more strategically about transitioning from a reliance on foreign aid to more mutually beneficial relationships with foreign countries. There are structural challenges to mobilizing domestic resources that long have been the focus of DRM efforts; however, addressing the political economy and structural challenges will be critical in the face of increased need and plateauing levels of foreign aid. It is critical that development approaches create the foundational capabilities and systems necessary to capitalize on political windows of opportunity.