Industrial ecologists are becoming interested in better understanding the influences on industrial structure and performance. It is clear that agency exists at several levels, with the fundamental sources of agency in industrial ecosystems being individuals acting as citizens, employees, investors, and consumers. Nations are the key actors on the global stage, but national policies emerge in part from interactions among citizens and organizations. Firms are key actors within sectors, supply chains, and symbioses. Corporate behavior, to some extent, emerges from interactions among employees, and market outcomes emerge from the myriad choices of individual consumers.