The term industrial ecology was conceived to suggest that industrial activity can be thought of and approached in much the same way as a biological ecosystem and that in its ideal form it would strive toward integration of activities and cyclization of resources, as do natural ecosystems. Beyond this attractive but fuzzy notion, little has been done to explore the usefulness of the analogy. This paper examines the structural framework of biological ecology and the tools used for its study, and it demonstrates that many aspects of biological organisms and ecosystems (for example, food webs, engineering activities, community development) do have parallels in industrial organisms and ecosystems. Some of the tools of biological ecology appear to be applicable to industrial ecology, and vice versa. In a world in which no biological ecosystem is free of human influence and no industrial ecosystem is free of biological influence, it is appropriate to abandon the artificial division between the two frameworks and develop a new synthesis-Earth system ecology-as the logical construct for all of Earth＇s ecosystems.