Thomas Hartung, MD PhD, is the Doerenkamp-Zbinden-Chair for Evidence-based Toxicology in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health, Baltimore, with a joint appointment at the Whiting School of Engineering. He also holds a joint appointment for Molecular Microbiology and Immunology at the Bloomberg School. He is adjunct affiliate professor at Georgetown University, Washington D.C.. In addition, he holds a joint appointment as Professor for Pharmacology and Toxicology at University of Konstanz, Germany; he also is Director of Centers for Alternatives to Animal Testing (CAAT, http://caat.jhsph.edu) of both universities. CAAT hosts the secretariat of the Evidence-based Toxicology Collaboration (http://www.ebtox.org) and manages collaborative programs on Good Read-Across Practice, Good Cell Culture Practice, Green Toxicology, Developmental Neurotoxicity, Developmental Immunotoxicity, Microphysiological Systems and Refinement. As PI, he headed the Human Toxome project funded as an NIH Transformative Research Grant and the series of annual Microphysiological Systems World Summits starting in 2022 by 52 organizations. He is Field Chief Editor of Frontiers in Artificial Intelligence. He is the former Head of the European Commission’s Center for the Validation of Alternative Methods (ECVAM), Ispra, Italy, and has authored more than 630 scientific publications with more than 42,000 citations (h-index 106). His toxicology classes on COURSERA had more than 16,000 active learners.