President and Chief Executive Officer, Deere & Company

Director, Global Carbon Measurement Program, The William J. Clinton Foundation

President, Center for Global Development

Former Deputy Under Secretary of Defense for Environmental Security

Former United States Senator, Nebraska

Former Secretary of Labor

Chairman, President and CEO, American Electric Power

Former U.S. Ambassador to the United Nations

Director, National Museum of Natural History

Former Deputy Secretary of the Interior

Former Chief of Staff, United States Army

CEO, The Nature Conservancy