They have made a difference and revolutionized the world. They come from all walks of life and from all corners of the globe. These remarkable individuals have pioneered, developed, and forever improved their industry and world in which we live. Engaging and relevant, these individuals will change the way you view the world and remind you that it only takes one person to make a difference. This episode features Richard Leakey, Steve Irwin, Al Gore, Wangari Maathai, and Leonardo DiCaprio.

Originally released by Film Ideas, 2011. Streaming video file encoded with permission for digital streaming by Infobase on March 10, 2015.

Richard Leakey: Conservationist (1:35); --Richard Leakey: Politician (2:42); -- Steve Irwin: Conservationist (1:32); -- Steve Irwin: Pop Culture Figure (2:49); -- Al Gore: Environmental Activist (2:42); -- Al Gore: Environmental Advocate (1:40); -- Wangari Maathai: Environmental Activist (1:55); -- Wangari Maathai: Visionary Environmentalist (2:21); -- Leonardo DiCaprio: Actor and Activist (1:36); -- Leonardo DiCaprio: Promoter of Green Causes (2:43); -- Credits: Environmentalists (Richard Leakey, Steve Irwin, Al Gore, Wangari Maathai, Leonardo DiCaprio): Advocates of Change (0:32); .