Mark Lawrence is director of the cluster “Sustainable Interactions with the Atmosphere” (SIWA) at the Institute for Advanced Sustainability Studies (IASS). SIWA focuses on the impacts and mitigation of short-lived climate-forcing pollutants, particularly in the face of global urbanization, and the potential impacts, uncertainties, and risks of “climate engineering.” His PhD in earth and atmospheric sciences is from the Georgia Institute of Technology in Atlanta. His research was conducted mainly at the Max Planck Institute for Chemistry in Mainz, Germany, where he later took over the atmospheric modeling group in the Atmospheric Chemistry Department. An awarded teacher, in 2009–10 he served as an interim professor for meteorology at the University of Mainz. Mark has authored or coauthored over 100 peer-reviewed publications and edited the journals Atmospheric Chemistry and Physics and Atmospheric Environment. He co-coordinated the European Union 7th Framework Project MEGAPOLI (2008–11), now coordinates the EU project EuTRACE (European Transdisciplinary Assessment of Climate Engineering), and has served or serves on various international committees, most notably the Science Team of the United Nations Environment Programme’s (UNEP) Atmospheric Brown Clouds project (ABC), the Scientific Steering Committee of the International Global Atmospheric Chemistry project (IGAC), and the Commission on Atmospheric Chemistry and Global Pollution (CACGP).