World orders are increasingly contested. As international institutions have taken on ever more ambitious tasks, they have been challenged by rising powers dissatisfied with existing institutional inequalities, by non-governmental organizations worried about the direction of global governance, and even by some established powers no longer content to lead the institutions they themselves created. For the first time, this volume examines these sources of contestation under a common and systematic institutionalist framework. While the authority of institutions has deepened, at the same time it has fuelled contestation and resistance. In a series of rigorous and empirically revealing chapters, the authors of Contested World Orders examine systematically the demands of key actors in the contestation of international institutions. Ranging in scope from the World Trade Organization and the Nuclear Non-proliferation Regime to the Kimberley Process on conflict diamonds and the climate finance provisions of the UNFCCC, the chapters deploy a variety of methods to reveal just to what extent, and along which lines of conflict, rising powers and NGOs contest international institutions. Contested World Orders seeks answers to the key questions of our time: Exactly how deeply are international institutions contested? Which actors seek the most fundamental changes? Which aspects of international institutions have generated the most transnational conflicts? And what does this mean for the future of world order?