The negotiations for the Global Plastics Treaty (GPT) that collapsed on December 2, 2024, were meant to be a step toward a plastics future informed by sustainable development principles. Given that no agreement has yet been reached, this Comment will discuss two broad issues that future GPT negotiating sessions must confront to produce an effective plastic life-cycle governance instrument. Part I reviews the fragmentation in current plastic waste-related governance instruments and institutions, and describes opportunities for the GPT to find synergies with those instruments. Part II discusses key sustainability issues—extended producer responsibility (EPR), circular waste management, and developed-developing world cooperation—that should drive a future agreement, and considers their interaction with the presently fragmented plastics governance system. Part III concludes.