Georges Vachaud is Director of Research Emeritus of the CNRS and has spent his entire career in the Laboratoire d’étude des Transferts en Hydrologie et Environnement (LTHE), which became the institut des géosciences de l’environnement (IGE) on 1 January 2017 after merging with the Laboratoire de Glaciologie et Géophysique de l’Environnement (LGGE). He has been responsible for numerous interdisciplinary research programs on transfers in unsaturated soils, aquifer contamination and the impact of urban development on surface water contamination, particularly in Asia. His work has earned him the CNRS Silver Medal (1977); the EUG Darcy Medal, 2003; the R.S. Vietnam Science Medal (2005); the Grand Prix (Dolomieu) of the Académie des Sciences (2012).