Economic growth-the increase in production and consumption of goods and services-must be considered within its biophysical context. Economic growth is fueled by biophysical inputs and its outputs degrade ecological processes, such as the global climate system. Economic growth is currently the principal cause of increased climate change, and climate change is a primary mechanism of biodiversity loss. Therefore, economic growth is a prime catalyst of biodiversity loss. Because people desire economic growth for dissimilar reasons-some for the increased accumulation of wealth, others for basic needs-how we limit economic growth becomes an ethical problem. Principles of distributive justice can help construct an international climate-change regime based on principles of equity. An equity-based framework that caps economic growth in the most polluting economies will lessen human impact on biodiversity. When coupled with a cap-and-trade mechanism, the framework can also provide a powerful tool for redistribution of wealth. Such an equity-based framework promises to be more inclusive and therefore more effective because it accounts for the disparate developmental conditions of the global north and south.