The increasing use of transnational standard-setting bodies to address quality uncertainties and coordination issues across the global economy raises questions about how these bodies establish and maintain their legitimacy and accountability outside the sovereignty of democratic states. Based on a discussion of the legitimacy challenge posed by global governance, we provide an overview of mechanisms by which such bodies can defend their legitimacy claims and examine the actual mechanisms used by the International Accounting Standards Board (IASB). While the IASB staked (...) its initial credibility on technical competence and independence, it has increasingly emphasized due process norms in its claim for support. Our analysis evaluates the IASB due process against the cultural benchmarks established by domestic standard-setters in the USA and UK and against a normative model of procedural legitimacy. These comparisons help us to understand the modifications that were made in the hope of due process adding legitimacy to accounting standard-setting beyond the state. They also reveal the broader political context of competing legitimacy criteria that confronts transnational standard-setters. (shrink)