When designing a world trading system for the twenty-first century, “Keep calm and carry on” beats “Move fast and break things.” Global trade is in trouble. Climate change, digital trade, offshoring, the rise of emerging markets led by China: Can the World Trade Organization (WTO), built for trade in the twentieth century, meet the challenges of the twenty-first? The answer is yes, Robert Staiger tells us, arguing that adapting the WTO to the changed economic environment would serve the world better than a radical reset. Governed by the WTO, on the principles of the General Agreement on Tariffs and Trade (GATT), global trade rules traditionally focus on “shallow integration”—with an emphasis on reducing tariffs and trade impediments at the border—rather than “deep integration,” or direct negotiations over behind-the-border measures. Staiger charts the economic environment that gave rise to the former approach, explains when and why it worked, and surveys the changing landscape for global trade. In his analysis, the terms-of-trade theory of trade agreements provides a compelling framework for understanding the success of GATT in the twentieth century. And according to this understanding, Staiger concludes, the logic of GATT's design transcends many, if not all, of the current challenges faced by the WTO. With its penetrating view of the evolving global economic environment, A World Trading System for the Twenty-First Century shows us a global trading system in need of reform, and Staiger makes a persuasive case for using the architecture of the GATT/WTO as a basis for that reform. “In this superb book, Robert Staiger applies rigorous economic analysis to key institutional design issues facing the international trading system, including climate change, digital trade, and the rise of China.  Original and important insights abound.” —Alan Sykes, Professor of Law, Stanford University   “From China to global supply chains to the digital economy to climate change, Staiger masterfully uses economics to explain the challenges confronting today’s trading system. An essential read for economists, political scientists, and legal scholars.” —Chad P. Bown, Reginald Jones Senior Fellow, Peterson Institute for International Economics   “More than thirty years ago, Robert Staiger embarked on a monumental research journey aimed at exploring the deep underpinnings of international trade agreements. This lucid book reviews much of this work and proceeds to study some aspects of trade agreements that will be most relevant in the 21st century. Academics and practitioners will greatly benefit from the insights of one of the shrewdest trade-policy experts in the world.” —Pol Antràs, Robert G. Ory Professor of Economics, Harvard University   “A world-leading authority on the law and economics of the WTO forcefully refutes current gloomy views on the future of agreement by systematically explaining how the WTO’s basic structure is well designed to also address twenty-first-century problems.” —Henrik Horn, Professor of International Economics, Research Institute of Industrial Economics, Stockholm Robert W. Staiger is Roth Family Distinguished Professor in the Arts and Sciences and Professor of Economics at Dartmouth College and a Research Associate of the National Bureau of Economic Research.