William Roos is Assistant Secretary for Multilateral, Development and Trade Affairs at the French Treasury, co-chair of the Paris Club and co-chair of the G20 International Financial Architecture Working Group. He previously served as Director for France at the Board of Directors of the European Bank for Reconstruction and Development, as Economic Counsellor for Southern Africa at the Embassy of France in Pretoria and as Head of International and Domestic Macroeconomic Policy Department at the French Treasury. William Roos holds a Master of advanced studies in industrial economics, microeconomics and econometrics from the Sorbonne University and from the National School of Statistics and Economic Administration (ENSAE-Paris Tech).