The University of Toronto Institute for Aerospace Studies (UTIAS) hosted its 5th International Workshop on Aviation and Climate Change during May 18-20, 2016. Held every two years since 2008, the workshop provides a snapshot of progress toward reducing the contribution of aviation to climate change even as the demand for air travel grows. The goal is to stimulate dialogue among academia, government, and industry toward finding technological solutions to reduce greenhouse gas emissions from aircraft. Consisting of 21 invited presentations and two roundtables, the workshop brings together some of the world’s leading experts in order to exchange ideas, establish research priorities, and identify opportunities for collaboration. Topics discussed include aircraft design, engine design, biofuels, atmospheric science, regulatory issues, and market-based measures. This year’s participants included representatives of the following organizations: NASA, University of Poitiers, Greener By Design, Pratt & Whitney (US), Lockheed-Martin, Shell, Aurora Flight Sciences, University of Michigan, Transport Canada, FAA, Bombardier Aerospace, University College London, DLR, Georgia Institute of Technology, Pratt & Whitney Canada, Massachusetts Institute of Technology, Airbus, and of course UTIAS. Professor and UTIAS Director David Zingg, who has organized all of the workshops, observed in his concluding remarks, “Every two years we have to ask whether we are advancing quickly enough to achieve the aviation sector’s ambitious target of a 50% reduction in total carbon dioxide emissions by 2050 relative to 2005. This year’s workshop provided cause for optimism, as a wide array of promising technologies are under active study and development. Governments around the world are making significant investments toward the target. Continued investment remains urgent, however, as it is critical that new technologies become available in the next 15 years in order that they can work their way into the global fleet in significant quantities by 2050.” The next workshop will be held at UTIAS in 2018.