Tom Ashbrook

Former Host of NPR's "On Point"

Ira Flatow

NPR Science Correspondent, Host of "Science Friday;" Science Media Expert

Mara Liasson

National Political Correspondent for NPR

Steven Squyres

Scientific Investigator, NASA

Rose Mapendo

Humanitarian / Activist / Congolese Genocide Survivor

Carmen Wong Ulrich

Personal Finance Expert

Elizabeth Cohen

Senior Correspondent for the CNN Health, Medical, & Wellness Unit

Elizabeth Cohen - CNN news story on baby formula shortage

Talib Kweli

Rapper, Emcee, Activist & Entrepreneur

Beth Simone Noveck

Founder & Director of The Governance Lab; Professor & Author of "Solving Public Problems"

Dr. Samantha Nutt

Medical Doctor, Award-Winning Humanitarian, Bestselling Author & Founder of War Child USA

Stacey Bess

Award-Winning Educator; Keynote Speaker; Advocate for Homeless Youth

Shirin Ebadi

Nobel Peace Prize-Winning Iranian Activist & Lawyer

Raj Patel

Award-Winning Writer, Food Politics Activist, Filmmaker & Academic

Ethan Zohn

Winner of "Survivor" Africa, 2x Cancer Survivor, Stem Cell Transplant Recipient, Social Entrepreneur, Philanthropist, Cancer Research Advocate, Former Pro Soccer Player, Sports Broadcaster & TV Personality

Rachel Simmons

Internationally Recognized Educator & Best-Selling Author

John Zogby

Trendspotter & Leading Pollster

John Prendergast

Human Rights Advocate and Author of Unlikely Brothers

Brad Meltzer

Host of History Channel’s "Lost History" & "Brad Meltzer’s Decoded;" New York Times Best-Selling Author

Graham Hill

Founder of Life Edited & TreeHugger.com

Mariane Pearl

Widow of Journalist Daniel Pearl