Walt joined the David and Lucile Packard Foundation in 2006 and is the director of the Conservation and Science Program.
Prior to joining the Foundation, he was a consulting professor with the Institute for the Environment at Stanford University from 2005 to 2006. Walt was responsible for the creation of the Millennium Ecosystem Assessment, which he directed from 1998 until the release of the findings in March 2005. From 1992 to 1998, he was vice president of the World Resources Institute in Washington D.C.
Walt is the Chair of the Board of the Climate and Land Use Alliance, a member of the Board of “The Economics of Ecosystems and Biodiversity” project; a member of the task team overseeing an International Council for Science process to develop global environmental change research priorities; a member of the Biodiversity and Ecosystem Services working group of the President’s Council of Advisors on Science and Technology (PCAST); a member of the Board of Editors of Ecosystems and PLOS-Biology, a member of the International Advisory Board of Frontiers in Ecology and Environment, and a past member of the Board of the Society for Conservation Biology and the Board of Editors of Ecological Applications.