By Amy Lawrenson

Last night Mary-Kate Olsen stepped out at the Council of Fashion Designers of America Awards in New York with a sleek, brunette hairstyle. The new look is a drastic change from her trademark beachy blonde tresses but it really suits her; it's a great improvement on the slightly scarecrow-esque hairstyle she showed off at the MET Ball just last month.

The Olsen sisters scooped the Womenswear Designer Of The Year award at the CFDA Awards ceremony held in Manhattan's Lincoln Center; the duo are the creative brains behind labels Elizabeth and James (named after their siblings) and The Row. Both Mary-Kate and Ashley were dressed in The Row 2013 Resort collection paired with Sidney Garber jewellery.

Brunette hair seems to be having a moment right now, Rihanna quickly abandoned her peroxide hair in favour of her natural dark brown hair colour, while Cheryl Cole recently went back to her roots for her latest single Call My Name.

I don't know what prompted Mary-Kate's sophisticated new look (who is 26 next week), but it could have something to do with her new older beau - former French president Nicholas Sarkozy's 42-year old half brother Olivier Sarkozy. Her new look is certainly more grown-up, we wonder how long it will last? (The hairstyle that is, not the relationship...)

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