Perspectives on Politics

Research Article

The Regime Complex for Climate Change

Robert O. Keohanea1 and David G. Victora2

a1 Woodrow Wilson School of Public and International Affairs, Princeton University. E-mail:

a2 University of California—San Diego. E-mail:


There is no integrated regime governing efforts to limit the extent of climate change. Instead, there is a regime complex: a loosely-coupled set of specific regimes. We describe the regime complex for climate change and seek to explain it, using interest-based, functional, and organizational arguments. This institutional form is likely to persist; efforts to build a comprehensive regime are unlikely to succeed, but experiments abound with narrower institutions focused on particular aspects of the climate change problem. Building on this analysis, we argue that a climate change regime complex, if it meets specified criteria, has advantages over any politically feasible comprehensive regime. Adaptability and flexibility are particularly important in a setting—such as climate change policy—in which the most demanding international commitments are interdependent yet governments vary widely in their interest and ability to implement them. Yet in view of the serious political constraints, both domestic and international, there is little reason for optimism that the climate regime complex that is emerging will lead to reductions in emissions rapid enough to meet widely discussed goals, such as stopping global warming at two degrees above pre-industrial levels.

(Online publication March 15 2011)

Robert O. Keohane is Professor of Public and International Affairs at the Woodrow Wilson School of Public and International Affairs, Princeton University (

David G. Victor is Professor of Political Science at the University of California—San Diego (


The authors are indebted for comments on an earlier draft to a number of colleagues, notably: Liliana Andanova, David Driesen, Robert Fri, Kelly Sims Gallagher, Jessica Green, Thomas Hale, Madeline Heyward, Ethan Kapstein, Yon Lupu, Kiran Magiawala, Ronald Mitchell, Michael Oppenheimer, Mihaela Papa, Kal Raustiala, and Burton Richter. They are particularly grateful to Jeff Isaac and three reviewers at Perspectives on Politics for their detailed comments. They also thank participants at various seminars and colloquia: at the Woods Institute, Stanford University, December 2009; the University of Texas, Austin, and Arizona State University, January 2010; New York University, February 2010; Princeton University, March and October 2010; University of California—San Diego Laboratory on International Law and Regulation, May 2010; and Columbia University, September 2010. The authors would also like to thank Linda Wong for research assistance.