TAYLOR SWIFT

The singer, who appears to still be in breakover mode, steps out in a silver dress with a whiplash-inducing neckline and bronze sandals at the 40 Principales Music Awards in Madrid.

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JENNIFER LOPEZ

Celebrating the Parker premiere in Las Vegas, J.Lo slips into a sheer paneled KaufmanFranco column gown (plus a Ferragamo clutch and Demarco earrings) and puts her famous curves on full display.

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ALICIA KEYS

Skin is apparently very in! Also at the 40 Principales Music Awards, the singer wears an equally revealing look: a black dress with sheer panels, plus strappy heels and statement earrings.

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DEMI MOORE

Another example of looking better after a breakup: Demi is all smiles in her waffle-print black dress and thigh-high open-toe boots (all by Ferragamo) at the Ferragamo Spring Runway Collection VIP Dinner in L.A.

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KATE HUDSON

Let's hear it for the boys. The boys-inspired fashion, that is. The actress suits up at the Raise Your Voice benefit in Beverly Hills, selecting a black blazer with a printed blouse, black pants and peep-toe pumps.

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NICOLE RICHIE

There's so much going on with this outfit, we almost didn't notice her new hair! Nicole attends the Ferragamo VIP dinner in all-black ensemble featuring a furry bodice, sheer polka-dot sleeves, a leather pencil skirt and studded heels and a white clutch (both by Ferragamo).

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ROSE BYRNE

The actress keeps it fresh and feminine in a simple pink Balenciaga dress, black Charlotte Olympia pumps, Dana Rebecca Designs jewelry and a black-and-white Thalé Blanc clutch at the London premiere of I Give it a Year.

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KIERNAN SHIPKA

Looking way more sophisticated than we ever did at 13, the Mad Men starlet takes tween style to the next level in a pink beaded gown, Kwiat jewels and silver Rupert Sanderson sandals at the ELLE Women in Television Celebration in Hollywood.

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VANESSA HUDGENS

The actress adds a pop of color to the red carpet in a bright orange shirtdress, a leather jacket with multi-hued trim and a bib necklace by The 2 Bandits at the launch party for Nanette Lepore's JCPenney collection in N.Y.C.

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JESSICA ALBA

The actress leaves her poodle purse at home and opts for a more simple look at the Sundance A.C.O.D. premiere, wearing a black-and-white dress, silver snakeskin heels, a basic black clutch and glimmering gems (all by Christian Dior) plus an Iwona Ludyga Design bracelet.

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JENNIFER LOPEZ

Despite the below-freezing temps in N.Y.C., J.Lo brings the heat to the Cinema Society and Appleton Rum-sponsored Parker premiere in an all-white ensemble featuring a strapless peplum dress and strappy heels (both by Lanvin) and Demarco jewels.

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KATE BOSWORTH

One of the perks of being Kate is having the ability to pull off an out-there outfit like this. The actress steps out at Sundance's Big Sur premiere wearing a belted sleeveless turtleneck, a camel leather skirt and some very serious white booties, all by Calvin Klein Collection.

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ASHLEY TISDALE

The actress hits Hollywood's Movie 43 premiere in a Philip Armstrong black-and-white dress with lace detail, Norman Silverman earrings, a Lauren Merkin clutch and black sandals.

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CHLOË MORETZ

Also donning black and white at the Movie 43 premiere, the actress gets down to business in a white button-up with a black cropped jacket, cigarette pants and bow-topped heels, all by Dolce & Gabbana.

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OLIVIA PALERMO

The fashionista strikes a pose in an all-black ensemble with a fur vest, statement necklace, Montblanc watch and her favorite Manolo Blahnik pumps at the Montblanc VIP dinner in Geneva, Switzerland.

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ALI LARTER

The actress attends the L.A. Art Show opening night in a pale pink belted gown with minimal accessories and a flawless fresh face.

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CARRIE UNDERWOOD

Since she no longer has her official purse holder, the star's solution is to leave her bag behind and opt for impactful shoes instead – which she wears with a black-and-tangerine number (the skirt is Diane von Furstenberg) and choppy new bangs at a Grammy Nominee party in Nashville.

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DAKOTA FANNING

She may be promoting Very Good Girls at Sundance, but the elder Fanning sis shows off her darker side in a black crop top, Louis Vuitton skirt and black booties.

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MIRANDA LAMBERT

The notorious dog lover partners up with Pedigree at an event in Glendale, Calif., wearing a feminine floral-print Shoshanna shirtdress with a blue Candy necklace and chunky pink Brian Atwood heels.

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AMANDA SEYFRIED

Stumped on how to look chic in super-chilly weather? Take a cue from Amanda (in Sundance for her film Lovelace and layer a cute jacket (hers is Michael Kors) over a cozy sweater, then add warm pants and boots.

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KATE BOSWORTH

Also at Sundance, the actress stops by the Variety studio wearing a muted Mulberry watercolor-print shift with a ruffled front and comfy flat boots.

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EMMY ROSSUM

The Beautiful Creatures star lives up to the film's title in an elegant blue lace Catherine Deane dress with a leather yoke, nude pumps and hot coral lips, all spotted backstage at The Tonight Show With Jay Leno.

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JULIA STILES

There definitely aren't 10 things to hate about this draped crimson Valentina Shah number, chunky black Pelle Moda sandals and statement jewelry, worn by the star to the premiere of the Hallmark Channel's The Makeover.

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EVA LONGORIA

The actress breaks out the couture, wearing a strapless corseted peach Vivienne Westwood design and Martin Katz earrings, to host the Latino Inaugural 2013 event in Washington D.C.

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JULIANNE HOUGH

At the Toronto premiere of Safe Haven, the actress trades in her ball gown for a sleek rose-colored Zimmermann dress with a tulip cut, nude heels, a Le Vian ring and bright red lips.

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KERRY WASHINGTON

The Scandal actress stays warm in chilly D.C. in a red-and-black chevron plaid Michael Kors dress with leather sleeves, a House of Lavande shark's tooth necklace and knee-high boots at the Daily Beast's Bi-Partisan Inauguration Brunch.

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NAOMI WATTS

At the Sundance premiere of Two Mothers, the actress shuns traditional snow gear for something way more chic: a gray sweater worn over a Roland Mouret blue silk shirt, leather pants, a Jennifer Meyer necklace and on-trend wedge sneakers.

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EMILY BLUNT

The actress takes her LBD up a notch with a double belt and sparkly Graziela earrings at the London Film Critics Circle Film Awards.

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ALLISON WILLIAMS

Also amping up an LBD, the Girls star steps out in a studded black dress with coordinating black Jimmy Choo pumps at the Women in Washington brunch in D.C.

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ROSARIO DAWSON

The actress continues the trend of bringing Hollywood glamour to D.C., wearing a beaded Reem Acra dress with an ombré hemline, Graziela earrings and pink accessories at the Learn.Build.Create Inaugural Celebration.

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SOPHIA BUSH

She bangs! The actress (and her dramatic fringe) turn up the heat in a black beaded Lisa Ho mini, Foley + Corinna clutch, Ben-Amun bracelet and silver Jimmy Choo pumps at the Planned Parenthood & Rock the Vote party in D.C.

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GABRIELLE UNION

If you look up "fierce" in the dictionary, this photo would probably appear. The actress strikes a pose in a ruched purple Herve L Leroux gown, Le Vian earrings and a Carrera y Carrera ring at the BET Networks Inaugural Ball.

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SHAILENE WOODLEY

Well, this is one way to stay warm. The young star bundles up at the Sundance premiere of The Spectacular Now in a brown-and-black leather-sleeved jacket, a striped maroon-and-black scarf (both by Marni) and a pink knit hat.

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TAYLOR SWIFT

JENNIFER LOPEZ

ALICIA KEYS

DEMI MOORE

KATE HUDSON

NICOLE RICHIE

ROSE BYRNE

KIERNAN SHIPKA

VANESSA HUDGENS

JESSICA ALBA

JENNIFER LOPEZ

KATE BOSWORTH

ASHLEY TISDALE

CHLOË MORETZ

OLIVIA PALERMO

ALI LARTER

CARRIE UNDERWOOD

DAKOTA FANNING

MIRANDA LAMBERT

AMANDA SEYFRIED

KATE BOSWORTH

EMMY ROSSUM

JULIA STILES

EVA LONGORIA

JULIANNE HOUGH

KERRY WASHINGTON

NAOMI WATTS

EMILY BLUNT

ALLISON WILLIAMS

ROSARIO DAWSON

SOPHIA BUSH

GABRIELLE UNION

SHAILENE WOODLEY

More Photos

Mark & Isla: Scene Stealers

Thar She Shows!Star Wardrobe Malfunctions

Fashion Faceoff: Katharine vs. Cobie and More!

Thar She Shows!
Star Wardrobe Malfunctions