Even though International Relations (IR) research increasingly recognises the unprecedented urgency of environmental degradation and the resulting ecological injustices, only few IR scholars have probed into the role of economic growth as a fundamental driver of global unsustainability. We level two critiques at the field of IR from a post-growth perspective. First, most IR theories are complicit in naturalising economic growth as a fundamental condition of global order. Second, IR scholarship has neglected to engage seriously with post-growth thinking. What happens when we start to question the background economic assumptions of the current international system? How might a global politics of post-growth challenge and enrich IR and environmental politics? This Editors Forum brings together a diverse group of scholars from across the globe to reflect on these pertinent questions. As a whole, the Forum begins to address the complicity and neglect critiques. To varying degrees, each contribution considers what IR can learn from post-growth research (both conceptually and empirically), and vice versa. In this introductory article, we set the stage for such an engagement by reviewing an interdisciplinary body of relevant work and synthesising the key contributions from a total of seven Forum articles.