Over 2,500 international investment agreements govern trillions of dollars in foreign direct investment that crisscrosses the globe. Nonetheless, the international investment law regime formed by those agreements faces a legitimacy crisis. Critics argue that international investment treaties’ dispute-resolution mechanisms favor foreign investors and that their substantive obligations undermine countries’ sovereignty. As the world’s largest exporters and recipients of foreign direct investment, the European Union and United States hold the keys to reform. Until now, however, they have differed on solutions. A well-designed investment chapter in a free trade agreement between the European Union and United States could simultaneously resolve those differences and redirect the trajectory of international investment law.