Pierre-Louis Viollet graduated from Ecole Nationale des Ponts et Chaussées (Paris) in 1974, PhD at Paris 6 University (1977). He has been working with EDF R&D as a research engineer and head of the R&D Laboratory of EDF on Hydraulics and Fluid Mechanics in Chatou. In1994 he moved to a managerial position as deputy director of the Generation Plants Department of EDF R&D, then as Director of the Power Systems Department. In 2001 he was nominated Vice-President for R&D Laboratories, and since 2006 has been acting as VicePresident for R&D Coordination and Partnership of EDF R&D. He has supervised the creation of 11 common laboratories involving EDF R&D and French academic partners, as well as a common institute with the University of Karslruhe (Germany): the European Institute for Energy Research. P.-L. Viollet has been for many years Professor of Applied Fluid Mechanics as Ecole Nationale des Ponts et Chaussées (Paris), where he has been nominated Honorary Professor in 2008, and Scientific Committee Member. He wrote two tutorial books in fluid mechanics as well as two books on the history of water and fluid technologies. P.-L. Viollet is chairman of the scientific committee of "Société Hydrotechnique de France", and of the scientific committee for the "Baie du Mont Saint Michel" hydro-sediment management. He has been for three years member of the Technical Committee of the Energy Technologies Institute (UK). He is a member of the Engineering and Physical Sciences Research Council (UK), and of the Energy Committee of the "Agence Nationale de la Recherche" (France).