Lee is Hoffmann Distinguished Fellow for Sustainability at the London-based think tank Chatham House. She also chairs Chatham House’s Sustainability Accelerator Advisory Board. In addition, Lee is a member of the UK Global Resource Initiative Task Force, the UK Climate Change Committee’s International Advisory Group, and the Energy Foundation China Board. 

Lee is an acknowledged expert on environmental issues, climate policy, international trade, and China. Lee has previously served as Director of Climate Change and Resource Security Initiatives at the World Economic Forum, Research Director for Energy, Environment and Resources at Chatham House, and Team Leader of the EU–China Interdependencies on Energy and Climate Security project.