Thomas Heller has served as Executive Director of the non-governmental organization Climate Policy Initiative (CPI) since 2009.

Since 1979, Heller has been professor at Stanford University, where he has served as the Shelton Professor of International Legal Studies, Senior Fellow at the Freeman Spogli Institute for International Studies and at the Woods Institute for the Environment. Thomas C. Heller has focused his research on the rule of law, international climate control, global energy use, and the interaction of government and nongovernmental organizations in the developing world.

He has been a contributing lead author for the IPCC Assessment Reports, as well as a contributor to the Special Reports on Technology Transfer and Emissions Scenarios. Beginning in 2008, Heller was a core team member directing Project Catalyst—an analysis based project in support of the Copenhagen Climate process. He has advised the Secretary General of the United Nations on climate change and served with the Secretary-General’s High Level Commission on Climate Finance as Sherpa to George Soros.