Dimitri Zenghelis is Co-Head Policy at the Grantham Research Institute at the LSE. In 2014 he was Acting Chief Economist for the Global Commission on the Economy and Climate. He was recently Senior Economic Advisor to Cisco's long term innovation group and an Associate Fellow at the Royal Institute of International Affairs, Chatham House. Previously, he headed the Stern Review Team at the Office of Climate Change, London, and was one of the authors of the Stern Review on the Economics of Climate Change. Before working on climate change, Dimitri was Head of Economic Forecasting at HM Treasury