This working paper provides a broad picture of official financial flows for infrastructure development in developing countries by bilateral and multilateral development partners. Multilateral development banks are further examined in a special section. The paper offers an overview volumes and distributions of financial flows, including those channelled to private sector operations and those mobilised from the private sector by guarantees, syndicated loans and collective investment vehicles. This report, which builds on previous work on the topic, will contribute to research and policy dialogue on filling the financial gap in infrastructure in developing countries. It will also support the monitoring of Sustainable Development Goal 9 and the discussions of the G20 on infrastructure development.