Diana Panke and Sören Stapel published a new book on International Organizations and the management of regime complexity! As regime complexity is characterised by overlapping policy competencies and membership between international organizations (IOs), it is usually associated with negative effects, such as inefficiency and incompatible rules and norms. However, the authors argue that IOs can avoid negative side effects or even create positive benefits by actively managing regime complexity.

To explain under what conditions IOs disregard overlaps or manage them by resorting to confrontation or collaboration, this book addresses the following research questions:

• Why do organizations differ in their responses to overlaps? 
• Why do some opt for disregard while others choose confrontation or engage in collaboration? 

These questions are answered by studying a subset of IOs, namely regional international organizations (RIOs), which recruit their member states on the basis of geographic criteria. Theoretically, this work advances a selection model based on three junctures: saliency, ideological fit, and contextual uncertainties. Their combination influences whether overlapping RIOs disregard one another and do not actively manage regional regime complexity (low saliency), when they choose confrontation (high saliency but low ideological fit) and when they opt for one of two ways to engage in collaboration, namely coordination (high saliency, high ideological fit, limited contextual uncertainty), or cooperation (high saliency, high ideological fit, high contextual uncertainty). The corresponding hypotheses are comprehensively analyzed in qualitative case studies from Africa, the Americas, Asia, and Europe.

This book is published in the Transformations in Governance series of Oxford University Press.