Robert Gibbs
Longtime Advisor to President Barack Obama; White House Press Secretary, 2009-2011

Bill Frist
Former U.S. Senator and Majority Leader; Heart-Lung Transplant Surgeon

Victoria Kennedy
Co-Founder and Trustee of the Edward M. Kennedy Institute for the U.S. Senate

Nicholas Christakis & James Fowler
Science Magazine has dubbed co-authors Nicholas Christakis and James Fowler the "dynamic duo."

Lance Armstrong
7-time Tour de France winner; Cancer Survivor; Leader of the LIVESTRONG Movement

David Katz
One of America’s Top Physicians in Preventive Medicine; ABC News Medical Consultant

Ezekiel Emanuel
Special Advisor for Health Policy, for the White House Office of Management & Budget (2009-2011); One of the World’s Leading Scholars of Bioethics & Healthcare

Peter Orszag
Member of President Obama’s Cabinet and Director, Office of Mngmt & Budget, 2009-2010

Howard Dean
Long-Standing Champion of Healthcare Reform; Former Chairman, Democratic National Committee

Cokie Roberts
Political Analyst for ABC News; NPR Senior News Analyst

Karl Rove
Bestselling Author, Courage and Consequence; Fox News Contributor; WSJ Columnist

R. Glenn Hubbard
Dean, Columbia Business School; Former Chairman, White House Council of Economic Advisors