Mary-Kate Olsen - Hair
Credit: Dennis Van Tine/ABACAUSA.COM; Mark Von Holden/WireImage

Bye-bye blond hair, hello brunette! Mary-Kate Olsen debuted a cool chestnut hue at the annual CFDA Fashion Awards in New York City yesterday, where she and her twin sister walked away with the night's top prize, Womenswear Designer of the Year. Although the new shade is a change from her sunny highlights, it isn't her first time to go darker. Back in 2005, the star worked a spicy cinnamon, which she later changed to a warm brown. Tell us: Do you like her new look?

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