James Marsden
The actor opted for Alternative Apparel tee while walking his dog in Studio City, Calif.
Jenna Ushkowitz
Animal magnatism! The Glee actress looked comfy in her Cheetah Boxy Tee from Wildlife Works.
Sophia Bush
The One Tree Hill star is known for her eco-friendly ways it's no surprise the actress suited up in H&M Conscious Collection.
Zac Efron
Zac's choice of socially responsible Toms footwear—they're made from recyclable materials—just makes the sexy star even hotter.
Katy Perry
While she's been known to favor plastic minidresses with pictures of candy on them, the singer showcases green, wearable technology with a CuteCircuit LED dress at the 2010 Met Gala that got a lot of buzz.
Hayden Panettiere
The starlet hits the grocery store complete with her organic Gypsy 05 jacket and reusable bags. Way to save the planet, hon!
Jennifer Aniston, Cheryl Crowe, Mary Fanaro & Courtney Cox
This gaggle of famous gals all have one thing in common: their love of OmniPeace tops. The shirts are not only cute, they're also created using culturally and environmentally friendly materials and proceeds go to help fight poverty in Africa.
Kristen Stewart
When she's not vamping it up on the red carpet, the Twilight star loves to keep it cazh—this environmentally friendly Alternative henley, partially made of organic cotton and recycled polyester, totes suits K.Stew's style.
Sara Rue
The actress models a "Handle the Earth with Care" shirt by Dirtee Hollywood.
Lauren Conrad
While hosting a party in Las Vegas, L.C. proves she's style savvy in a striped Gypsy 05 maxidress.
Natalie Portman
The pregnant Oscar winner dons a recycled polyester sheath from the H&M Conscious Collection at a pre-Oscar event in Los Angeles, proving that this star is all about the green.
Keep clicking to check out some of the hottest eco-friendly trends the celebs can't get enough of!
Livia Firth
At the 2011 Academy Awards, the Oscar winner's wife created her dress using 11 recycled pieces from thrift stores and vintage shops. Not to mention, they were all from the era of The King's Speech. Talk about going the extra mile!
Maria Menounos
The TV correspondent shows off her green stems in M2F Brand denim, which is made with eco-friendly yarn and earth smart dye processes.