Cesar Millan

Host of The Dog Whisperer; Author of Cesar's Way

Lo Bosworth

Entrepreneur & Lifestyle Personality, Author, and Alum of MTV’s Reality Show, "The Hills"

David Suzuki

Environmentalist & Scientist; Co-Founder of the David Suzuki Foundation

Tamron Hall

Award-Winning Journalist; Former National News Anchor for NBC News; Host of the "Tamron Hall Show"

Watch Where They Hide

Eric Stonestreet

Actor & Comedian, Best-Known for "Modern Family"

Keegan-Michael Key

Actor, Producer, Writer & Comedian

Lynn Sherr

Award-winning Broadcaster & Best-selling Author; Correspondent 20/20

Kevin Nealon

Former Cast Member of 'Saturday Night Live'; Co-Star on Showtime's "Weeds"

Matt Damon

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

Alfonso Ribeiro

Host of America’s Funniest Home Videos, Actor, TV Director, Award-Winning Dancer & Broadway Star

Moby

Musician, DJ, Photographer

Alison Victoria

Interior Designer; Host of HGTV's "Kitchen Crashers"

Shaun Tomson

Former World Champion Surfer, Environmentalist & Motivational Speaker

Ashley Greene

Actress and model; best known for her recent roles in the "Twilight" series

Philippe Cousteau

Explorer, Social Entrepreneur & Environmental Advocate; Grandson of Captain Jacques-Yves Cousteau

David Doubilet

National Geographic Photographer & Founding Member of the International League of Conservation Photographers

Kristin Bauer van Straten

Best known as Pam on HBO's "True Blood"

Tamilee Webb

Fitness Expert & Instructor, Star of "BUNS OF STEEL"

Alan Cumming

Emmy-Winning Actor Who Stars in "The Good Wife"

Vandana Shiva

World-Renowned Environmental Leader