The Global Footprint Network (GFN) has calculated that humans currently use as much ecological resources today as if we lived on 1.6 Earths. According to the GFN the “Ecological Footprint is the only metric that compares the resource demand of individuals, governments, and businesses against Earth’s capacity for biological regeneration.” This presentation will discuss the GFNs tools for advancing sustainability, including the ecological footprint and biocapacity calculators, which measure the resources humans use and how much we have available. Can we use these tools to bring ecological limits to the center of decision-making?