The first history of the Export-Import Bank of the United States (Ex-Im) based on archival sources. As the government’s export credit agency (ECA), Ex-Im promotes exports through loans, guarantees, and insurance and has had an unusual history as a public institution shaped by market principles. Congress mandated that the Bank only provide credit with a reasonable assurance of repayment. But the rules of the market and the needs of the state conflicted at times. Ex-Im has played a part in all the major events that marked the growing involvement of the United States in the international economy. In the last two decades, the Bank has worked in an increasingly complicated environment brought on by changes in private capital markets; Congressional constraints on its budgets; major financial crises in Latin America and Southeast Asia; fast-moving developments in communications and information technology; and the demands of non-governmental organizations devoted to environmental protection.