The international economic system that emerged after the 1944 Bretton Woods conference became the most durable international arrangement devoted to economic openness. Seventy-five years after the conference, however, global shifts in power, institutional gridlock, and populist backlash figure prominently in accounts predicting the system's demise. This article examines the legacies of the Bretton Woods conference for structures and practices of global economic governance and innovations that emerged over time to adapt the system to new political and economic circumstances. It explores how and why the Bretton Woods system became a more variegated system over time with respect to four features of governance: membership, legalization, organizational focality, and market embeddedness. It identifies sources and effects of expanding membership in the International Monetary Fund and the World Bank, the emergence of new formal and informal institutions, the challenges of a more fragmented institutional landscape, and shifts in the underlying principles of economic governance. Finally, the article discusses lessons from past crises in and reforms to the Bretton Woods system, and their implications for understanding recent challenges to global economic cooperation.