Best Celebrity Hair Colors

Hayden Panettiere attends the unveiling of Stuart Weitzman's Young Hollywood Cares Collection in aid of ovarian cancer research during Fashion's Night Out in NYC.

Jennifer Aniston attends the UK premiere of Horrible Bosses at BFI Southbank on July 20, 2011 in London, England.

Cameron Diaz attends the New York premiere of Bad Teacher at the Ziegfeld Theatre on June 20, 2011 in New York City.

Actress Blake Lively arrives at the 2011 Teen Choice Awards at Gibson Amphitheatre on August 7, 2011 in Universal City, California.

Actress Salma Hayek boards a motorboat at a Venice hotel during the 68th Venice Film Festival on September 3, 2011.

Rachel Bilson arrives at the TCA party for CBS, The CW, and Showtime held at The Pagoda on August 3, 2011 in Beverly Hills, California.

Actress Megan Fox arrives at the Friends With Kids premiere at Ryerson Theatre during the 2011 Toronto International Film Festival.

Leighton Meester attends the launch of the HTC Rhyme in NYC on September 21, 2011.

Actress Jennifer Garner signs autographs for fans at the Butter premiere at Roy Thomson Hall during the 2011 Toronto International Film Festival.

Marcia Cross attends the 2011 NCR ALMA Awards at Santa Monica Civic Auditorium on September 10, 2011 in California.

Actress Julianne Moore attends the Reeve Foundation and Clark's Botanicals Night for a Cure Party at the Mondrian Soho hotel on September 7, 2011 in NYC.

Isla Fisher attends the 2011 Veuve Clicquot Polo Classic at Governor's Island on June 5, 2011 in New York City.

Emma Stone attends the opening ceremony for the 37th Deauville American Film Festival on September 2, 2011 Deauville, France.

Actress Christina Hendricks arrives at the premiere Of Iris—A Journey Into the World of Cinema By Cirque du Soleil at the Kodak Theatre on September 25, 2011 in Hollywood, California.

Kim Kardashian promotes the Kardashian Kollection at Sears on September 18, 2011 in Cerritos, California.

Jennifer Hudson attends the 2nd Annual amfAR Inspiration Gala at the Museum of Modern Art on June 14, 2011 in New York City.

Halle Berry shopping in Century City on July 26, 2011 in Los Angeles, California.

Demi Moore attends 3rd Annual Variety's Power Of Women Event Presented By Lifetime on September 23, 2011 in Beverly Hills, California.

Vanessa Hudgens attends the premiere of Iris—A Journey Into the World of Cinema By Cirque du Soleil at the Kodak Theatre on September 25, 2011.