Sophia Bush

Actress, Humanitarian & Author

Daryl Hannah

Actress, Best Known for "Kill Bill" & "Splash"; Environmental Activist

Alicia Silverstone

Actress & Animal Rights Activist

Alyssa Milano

Actress, Author, Philanthropist & Founder of Touch by Alyssa Milano; Known for "Charmed" and "Who's the Boss"

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

Brad Pitt

Actor, Producer, Philanthropist & Environmental Activist

Shailene Woodley

Actress & Environmental Activist

Cate Blanchett

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

Molly Sims

Actress, Model & Lifestyle Expert; Environmental & Ocean Activist

Hayden Panettiere

Actress Known for "Nashville" & "Heroes" & Animal Rights Activist

Ashley Judd

Actress, Activist & Humanitarian

Alysia Reiner

Actor, Activist & Entrepreneur

Patricia Arquette

Academy Award-Winning Actress, Activist, Humanitarian & Author

Marion Cotillard

Academy Award-Winning French Actress; Environmental Activist & Greenpeace Spokesperson

Matt Damon

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

Pink

Singer-Songwriter, Actress, Philanthropist & Environmental Activist

Mark Ruffalo

Actor, Director, Producer, Screenwriter & Environmental Activist

Ed Begley Jr.

Environmental Activist & Emmy Award-Nominated Actor

Lucy Lawless

Actress, Activist & Musician Best Known for Playing the Title Character in "Xena: Warrior Princess"

Katie Cleary

Actress and Model; Founder of Peace 4 Animals and World Animal News

Emmy Rossum

Actress Known for Showtime's "Shameless" & Singer-Songwriter

Ryan Reynolds

Producer, Screenwriter, Actor & Entrepreneur; Co-Owner of Welsh Football Club Wrexham A.F.C.

Alanis Morissette

Alt-Rock Angst Icon Known for "You Oughta Know" & "Ironic"

Alexandra Cousteau

Environmental Activist, Storyteller & Ocean Advocate

Emmanuelle Chriqui

Actress Known for "Entourage;" Social Advocate for Colon Cancer, Environmental Issues & Human Rights in Congo

Sheryl Crow

Grammy Award-Winning Singer-Songwriter

Alice Waters

Executive Chef, Founder & Owner of Chez Panisse; Sustainable Agriculture Advocate

Loretta Swit

Animal Activist & Emmy Award-winning Actress; Best Known for "M*A*S*H"

Ian Somerhalder

Actor Known for "The Vampire Diaries"; Animal & Environmental Advocate; Founder of The Ian Somerhalder Foundation