With great power comes great dispersion. How policy-cycle competences drive power dispersion in regional organizations

Do member states concentrate or disperse competences when delegating authority to regional organisations (ROs)? Existing scholarship has examined how much independence organizations enjoy from their members, but has paid little attention to how competences are distributed across an organization’s internal organs. This article addresses that gap by introducing measures of concentration and policy capacity alongside the established measure of scope, drawing on an original dataset of over 230 treaties covering the near-complete population of regional organizations since 1945. We find that while the scope and policy capacity of ROs have increased steadily over time, this expansion has been accompanied by a significant decline in concentration across most organizations. To explain this pattern, we test two competing theoretical accounts. Rational design theory predicts that member states deliberately disperse competences as a sovereignty-protecting response to increased delegation. Functional evolution theory predicts instead that dispersion emerges from the governance demands that broader scope places on organizational structures. Our empirical analysis supports the functional account: policy capacity mediates the relationship between scope and concentration, and institutional complexity – rather than political scope – is the primary driver of dispersion. Member states do not merely delegate; they simultaneously design internal structures that distribute competences across specialized organs.