A great transformation is under way in international relations. The influence of non-state actors is rising, and the focus of intergovernmental coordination is shifting from border measures, such as tariffs, to a myriad of policies that traditionally have been the sole province of national decision making, such as food safety standards. This transformation is most evident where international cooperation has been most successful: international trade, in particular the efforts within the World Trade Organization (WTO) to manage non-tariff barriers to trade. In many cases it has proved extremely difficult for nations to comply with WTO strictures on non-tariff policies because these policies are embedded within an array of political supporters and institutions that democratic governments find difficult (and politically costly) to unravel. We focus on these “problem cases”—where the goal of liberalizing trade conflicts with popular consumer preferences—and suggest that these pose a threat to the legal integrity and political sustainability of the WTO. Ironically, cases marked by relatively low economic stakes may pose the greatest threats because these cases are less likely to be linked to other important benefits of international cooperation, and thus governments are less likely to seek an intergovernmental solution to avert non-compliance in such situations. We suggest that formal remedies to this problem are unlikely to be successful; rather, restraint by key states is likely to be the most effective way for the world trading community to learn to avoid and abate these problem cases before they overwhelm the world trading system.