Author info: Laurent Charlet is a Distinguished Professor, Universite Joseph Fourier Grenoble I in France, and an expert in contaminant geochemistry, particularly with respect to arsenic and selenium. Author of more than 120 publications, his research encompasses both molecular-scale modeling and field-scale descriptions of hydrogeology and contaminant availability. He has established research and education programs in Laos and Cambodia. He is also Editor-in-Chief of Hydrology, and manager of several French and EU research initiatives. In 2007, Laurent received the CNRS Silver Medal, one of France’s highest research honors.