Dr. Mathis Wackernagel created the footprint concept in the early 1990s (with Prof. William E. Rees) to compare human demand against planetary or regional ecosystem regeneration. This tool allows researchers to track global overshoot and countries’ ecological deficit. The carbon footprint portion has become the most popular footprint variant. In 2003, he co-founded Global Footprint Network, a sustainability think-tank, making planetary constraints relevant to decision-making. Its largest engagement campaign is its annual Earth Overshoot Day. Mathis’s main interest is finding ways to turn overshoot into a magnet that motivates, rather than an “inconvenient truth” that triggers resistance. Mathis’s honours include the 2018 World Sustainability Award, the 2015 IAIA Global Environment Award, and the 2012 Blue Planet Prize as well as honorary degrees.