Brazil can expect significant benefits from joining the Organization for Economic Cooperation and Development (OECD). The organization has shown to effectively promote better policies and institutions among its members countries, with significant positive effects. Considering the evidence that institutions are behind a large share of long-term increases in welfare standards, the benefits of membership go well beyond the modest costs involved in participating in the organization. Among the studied benefits are increases in trade – which are larger than those due to other international organizations such as the World Trade Organization (WTO) or the International Monetary Fund (IMF) –, increases in foreign direct investment, improvements in education, and better results in governance. Risks are small compared to potential benefits. We estimate the benefits by benchmarking against an estimate of the benefits of acceding to an institution with similar goals and policies – the European Union (EU) – and find them to be very large.