KATIE HOLMES

Heading to her Broadway show, Dead Accounts, in N.Y.C., Katie keeps it casual and cool in an oversize navy jacket that shows off her gams, plus floral Pretty Polly tights and ankle booties.

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JESSICA CHASTAIN

Heading out after her Broadway show, the actress wears the official color of N.Y.C. women via a military-inspired coat, tights and lace-up platform booties, but adds visual interest with a leopard-print mini.

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NICKI MINAJ

No Christmas dresses here! Nicki gets festive with a black body suit featuring red-and-black studded shoulder pads, coordinating oversize sunglasses and black platforms at the Christmas Extravaganza at Webster Hall in N.Y.C.

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DEMI LOVATO

Demi has stuck to all-black ensembles for much of her X Factor stint, but for the show's L.A. finale, she dares to bare (and get people to stare) in a blue-and-copper cutout minidress, huge hoops and towering black pumps.

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KATIE HOLMES

Never one to follow traditional style rules, the star tops a feminine fuchsia Narciso Rodriguez dress and champagne bow-topped heels with an unexpected olive military-inspired trench before her appearance on The Late Show With David Letterman in N.Y.C.

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BRITNEY SPEARS

Brit, on the other hand, plays it safe for her final night on X Factor, accenting her black-and-sheer bustier dress with giant patent platforms and a flippy updo.

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TINA FEY

Tina says goodbye to 30 Rock in style, attending an N.Y.C. wrap party in a graphic-print top, jeans and heels.

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KHLOÉ KARDASHIAN

The X Factor judge also prepares to send off the show at its L.A. finale – but in a way more amped-up ensemble, from her green-and-pink shimmer mini dress to her giant curls.

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NAOMI WATTS

For her appearance on N.Y.C.'s The Late Show With David Letterman, the Impossible star beats the elements in a leather A-line Calvin Klein Collection coat, earrings and a ring by Jamie Wolf and a Joan Hornig cuff, and gold-piped booties.

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DEMI LOVATO

It's back to black for the X Factor judge, who celebrates the show's L.A. finale in a tuxedo jacket, chunky Karen London necklace and sky-high sandals.

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BRITNEY SPEARS

Combining a black backless top with a strikingly long chain of black beads and what appear to be the heel equivalent of Adidas Sambas, Brit makes her own unique style statement at the X Factor finale.

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KHLOÉ KARDASHIAN

The X Factor host is part sexy waitress, part beauty queen and part party girl in her black, white and shocking pink look at the show's L.A. finale.

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GIULIANA RANCIC

Miss Universe has nothing on the TV personality, who glides down the show's Las Vegas red carpet in a pageant-worthy strapless fishtail Winnie Couture dress and soft updo.

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LEANN RIMES

Prior to her buzzed-about performance on the X Factor finale, the star hits the red carpet in a black mini, knee-high boots and a fringed, beaded necklace.

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RITA ORA

There are holiday party outfits we enthusiastically recommend, and then there are other holiday party outfits. We'll let you decide which category Rita's embroidered shimmering mini and knee-high chain peep-toe booties, worn to a West Hollywood charity event hosted by Samsung Galaxy and the Weinstein company, fall under.

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RIHANNA

During the finale of The Voice, Rihanna hits the stage in a dazzling sequin jumpsuit, striking crystal accessories and bronze sandals (all by Lanvin), plus a J/Hadley snake ring.

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ROSE BYRNE

She's at an N.Y.C. screening for Not Fade Away, but Rose's outfit would work equally well for a low-key holiday outing: the all-black outfit is a no-brainer, while the pops of red and snakeskin heels make it feel festive.

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BELLA HEATHCOTE

Also at the Not Fade Away premiere (and also opting for a red-and-black palette), the film's star looks elegant in a two-tone draped Lanvin gown, Swarovski earrings and on-trend wine lips.

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NICKY HILTON

In N.Y.C. to help pal Derek Blasberg launch his stationery collection for Opening Ceremony, the star balances cozy with cute in a striped knit sweater, gray jeans and chain-adorned booties.

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PETRA NEMCOVA

The supermodel gets decked out in appropriately uplifting colors at a Miami event to celebrate her Happy Hearts Fund's new partnership with Clinique. She finishes her look with neutral pumps and a delicate pendant.

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ALEXA CHUNG

Opting for a less cheerful look than Petra, the British style setter flashes a bit of skin in a head-to-toe black ensemble at Derek Blasberg's Opening Ceremony party in the Big Apple.

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BRITNEY SPEARS

Looking bangin' at the L.A. X Factor season finale, the show's judge shows off her curves in a fitted black sheath, sparkling necklace and high-shine sandals.

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JESSICA CHASTAIN

The Zero Dark Thirty star also opts for an LBD (this one plunging, with a peplum) and pretty Casadei sandals at an N.Y.C. screening of the film.

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ASHLEY TISDALE

Ashley does good while looking good, wearing a body-con white mini with layered necklaces and cheetah-print platforms at a Toys for Tots holiday party in Studio City, Calif.

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HAILEE STEINFELD

What, like you didn't celebrate your Sweet Sixteen in Louis Vuitton? The actress pairs her checked romper and red clutch by the luxe label with tri-tone pumps, all worn to her VitaminWater and Sally Hansen-sponsored birthday bash in L.A.

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DEMI LOVATO

Brit's cohort on the X Factor fêtes the final episode of the season in a striped skirt, blousy black top and collar necklace.

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KHLOÉ KARDASHIAN

Also at the X Factor finale bash, the show's host tops her flattering all-black ensemble with a leopard jacket and some serious pageant hair.

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MILEY CYRUS

Taking her role as a VH1 Diva very seriously, the star makes an entrance at the L.A. concert in a black turtleneck dress that shows off her toned bod via some very racy cutouts, plus Jean-Michel Cazabat pumps and Lorraine Schwartz earrings and bracelet with an Ofira ring.

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DUCHESS CATHERINE

What baby bump? The expectant royal looks slim as ever in an elegant forest green V-neck Alexander McQueen gown, worn to her first public appearance since announcing her pregnancy: the BBC Sports Personality of the Year Awards in London.

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DEMI LOVATO

Also at L.A.'s VH1 Divas event – but looking decidedly less dramatic than Miley – the singer shines in a holiday party-perfect dress with a reverse scoop neckline and sheer beaded sleeves.

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CAREY MULLIGAN

The Great Gatsby star also opts for sheer, black and sparkly at a Gstaad Alzheimer's benefit, wearing a glittering checked dress with studded sandals and a slicked-back bun.

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KELLY OSBOURNE

In a floaty white Paule Ka dress and flirty, feathery Charlotte Olympia pumps (plus, yes, that purple hair), the star is all smiles at the VH1 Divas event in L.A.

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KRYSTEN RITTER

Yet another way to another way to accessorize an LBD! The actress celebrates her birthday in Las Vegas with a gladiator-inspired Hervé Léger by Max Azria dress, Rachel Zoe Collection boots and lots of sparkle.

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JORDIN SPARKS

Joining the rest of the crew at the VH1 Divas concert in L.A., the singer chooses an elegant black Nicole Miller gown with bronze embellishments and a Daniel Swarovski clutch.

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KERRY WASHINGTON

The Django Unchained actress stops by BET's 106 & Park sporting a leather A.L.C. LBD with edgy accessories (including a House of Lavande Vintage necklace, and necklaces, a bracelet and rings all by Sydney Evan) and contrasting ladylike pumps.

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LINDSAY LOHAN

If you think the actress has a lot going on in her personal life, the same can be said about her outfit — a black mini with lace sleeves and a leather and fur jacket — which she wore to a holiday party in N.Y.C.

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JENNA DEWAN-TATUM

The wife of the Sexiest Man Alive hides her growing baby bump in a strapless empire waist Temperley London dress and dazzling accessories (including an Oroton clutch) at the VH1 Divas concert in L.A.

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