Sebastian re-joined the GSG in January 2020 as Chief Policy Officer. Prior to that he was Secretary of State for Socio-Urban Integration at Argentina’s Ministry of Health and Social Development, designing and leading an ambitious programme to urbanize over 4,400 slums and informal settlements across the country. Previously, Sebastian served at Argentina’s Cabinet Office, was the founding Executive Director of the GSG and Chief Economist of The Portland Trust, a British NGO promoting peace and stability between Israelis and Palestinians through economic development. He holds a BA in Economics from the University of Buenos Aires (Argentina) and an MSc in Economic Development from the University of Sussex (UK). As an economist his career combines extensive field experience with policy and analytical work in economic development, impact investment, conflict economics and socio-urban development.