Global Green USA: Founded by former Russian President Mikhail Gorbachev as a means to solve the world's environmental challenges.

What They Do: Global Green USA is the national environmental affiliate working to stop global warming by creating green buildings and cities, eliminating weapons that threaten lives and the environment, and providing clean, safe drinking water to the 2.4 billion people worldwide who lack it.

Star Wattage: Global Green relies heavily on celebrity support from aforementioned Pitt, Charlize Theron, Morgan Freeman, Natalie Portman, Leonardo DiCaprio, Tom Hanks, Susan Sarandon and Salma Hayek.

Global Green USA Celebrities

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They arrive in eco-limos to awards shows. They live in solar-paneled homes, some even completely off the grid. They time their showers, they buy organic. And when it comes to philanthropic green crusades, many give because they can, give 'til it hurts, give from the heart.



Natural Resources Defense Council: The mother of all green organizations, Worth magazine named the NRDC one of America's 100 best charities, and the New York Times called it, "One of the nation's most powerful environmental groups."

What They Do: Boasting 1.2 million members and online activists, the NRDC employs environmental lawyers, scientists and lobbyists to champion issues from defending wildlife to protecting clean air and water. The three-decade-old nonprofit is making a difference: They have forced legal action on polluting oil companies, won commitments from companies such as Kinko's, Starbucks and Home Depot to phase out their use of old-growth wood products, and prevented the Bush administration's attempts to open the Arctic National Wildlife Refuge to oil drilling.

Star Wattage: Robert Redford, Leonardo DiCaprio and James Taylor are board members, along with other Tinsletown machers. The rock group Green Day joined forces with NRDC to bring its eco-message to their fans.

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