With its pioneering Tracking Underreported Financial Flows (TUFF) methodology, AidData shines a light on the activities of donors and lenders that do not fully participate in global reporting systems. We publish uniquely comprehensive and granular project-level datasets; create interactive dashboards and maps; and analyze the nature, scale, composition, and effects of underreported financial flows. We support government officials who need transparent data and tools to scrutinize incoming proposals and negotiate more favorable contracts. We are also engaged in a wide-ranging effort to understand the impacts of underreported development finance on environmental protection, public health, debt sustainability, socio-economic welfare, and governance.