The relationship between trade, investment, and environmental protection is complex, and environmental activists have engaged with international economic law in a wide variety of ways. Some environmental activists have sought to use trade systems as leverage to advance environmental protections aims, while others have been concerned about how international economic law constrains unilateral national environmental action. The dominant account of the harmonization of economic and environmental norms and the promotion of sustainable development through trade and investment is challenged by sobering statistics of ecological decline. In the face of intersecting ecological, economic, and social crises facing the global community, the often-marginalized critique developed by environmental justice activists of neoliberal globalization and the legal regimes that enable it is more urgent than ever. These perspectives and voices—which sometimes align with other environmental activists and sometimes directly oppose market-orientated environmental agendas—have been marginalized in the scholarship on international economic law, but offer an indispensable resource for imagining more equitable and ecologically just forms of global economic cooperation. This essay shows how environmental justice activists have enacted a powerful politics of refusal, resisting international economic law as well as articulating visions of how to achieve systemic change and sustainable societies based on environmental, social, economic, and gender justice and peoples’ sovereignty.