Arnold Schwarzenegger

Actor, Producer, Director, Writer; California’s 38th Governor; Host of "Celebrity Apprentice"

Al Gore

45th Vice President of the United States, Nobel Peace Laureate & Bestselling Author

Bono

Lead Singer of U2, Activist & Co-Founder of DATA (Debt, AIDS, Trade, Africa)

Matt Damon

Actor, Screenwriter & Producer; Co-Founder of Water.org; Expert Advocate on Global Water & Sanitation Crisis

Edward Norton

Award Winning Actor & Filmmaker

Leonardo DiCaprio

Award-Winning Actor & Environmentalist

Robert Redford

Actor, Director, Producer, Environmentalist & Founder of the Sundance Film Festival

Don Cheadle

Actor, Activist & Author; Known for "Iron Man 2" & "Hotel Rwanda"

Sheryl Crow

Grammy Award-Winning Singer-Songwriter

Cate Blanchett

Academy Award-Winning Actress Known for "Elizabeth" & "The Aviator;" Ambassador for the Australian Conservation Foundation

Olivia Munn

Television & Film Actress; Known for "Newsroom" & "X-Men: Apocalypse"

Olivia Munn on Jon Stewart | 2022 Mark Twain Prize

Pierce Brosnan

Actor, Producer & Activist; Best Known for His Role as James Bond

Shailene Woodley

Actress & Environmental Activist

Brad Pitt

Actor, Producer, Philanthropist & Environmental Activist

Jake Gyllenhaal

Academy Award-Nominated & BAFTA Award-winning Actor; Environmental Activist

Maroon 5

American Pop/Rock Band Known for the Hit Singles, "Maps," "Love Somebody" & "Misery"

Kimbal Musk

Chef, Restaurateur & Philanthropist

Livia Firth

Co-Founder & Creative Director of Eco-Age