Tansy Massey-Green

Tansy Massey-Green

Senior Associate
  • US Program

Tansy is a Senior Associate on the America Is All In team within the US Program at RMI. America Is All In is the largest, most diverse US coalition of leaders ever assembled in pursuit of climate action. Its mission is to take a whole-of-society approach to solving the climate crisis, in collaboration with the federal government. Tansy works on strategy, website development, communications, and signatory engagement.



Prior to joining RMI, Tansy was at the World Wildlife Fund working on the coalition We Are Still In, the group that formed when the Trump Administration withdrew from the Paris Climate Agreement and non-federal actors showed their leadership by staying committed to climate action. At the start of the Biden Administration, We Are Still In merged with America’s Pledge to form America Is All In.

Tansy started out her professional career in the Boston area at a buildings utility tracking and benchmarking startup called WegoWise. She later worked at the Union of Concerned Scientists.



B.S., Ecology and Evolutionary Biology, Environmental Studies, University of Michigan