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Michelle Obama wears a Marchesa gown to a state dinner honoring British Prime Minister David Cameron at the White House in Washington on March 14, 2012.
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President Barack Obama and first lady Michelle Obama enter the East Room with Israeli President Shimon Peres for a dinner where he would be presented with the Presidential Medal of Freedom June 13, 2012, at the White House in Washington.
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First lady Michelle Obama helps BET honoree poet Maya Angelou stand after receiving the Literary Arts Award during the BET Honors, at the Warner Theatre in Washington on Jan. 14, 2012.
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President Barack Obama and first lady Michelle Obama walk through the Cross Hall to the East Room of the White House on Feb. 29, 2012, in Washington.
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President Barack Obama and first lady Michelle Obama walk out to greet South Korean President Lee Myung-bak and his wife Kim Yoon-ok at the North Portico of the White House in Washington, Thursday, Oct., 13, 2011, prior to a state dinner.
Mrs. Obama donned a purple, one-shoulder jersey gown with a jeweled belt by Korean-American designer Doo-Ri Chung for the gala. She paired the dress with gold chandelier earrings and a gold cuff bracelet.
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For the state dinner at the White House in honor of German Chancellor Angela Merkel on June 7, 2011, first lady Michelle Obama stepped out in an all-over embellished gown by Naeem Khan. The ivory, v-neck column dress featured silver beads, white sequins and metallic thread in a geometric pattern. Tousled hair and a stack of chunky bangles by Alexis Bittar completed her look.
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Khan, an Indian-born American designer, also designed the nude-colored gown that Mrs. Obama wore for the first State Dinner she and husband President Barack Obama hosted for the Indian prime minister on Nov. 24, 2009.
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Mrs. Obama attended the Pritzker Architecture Prize Event at Andrew Mellon Auditorium, on June 2, 2011, in Washington with President Obama, wearing a floor-length blue, halter and belted gown by Reed Krakoff.
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Fashionistas were all over this red-and-black full-length gown by Sarah Burton of the British design house Alexander McQueen, which Mrs. Obama wore for the State Dinner with Chinese President Hu Jintao on Jan 19, 2011. The gown's color choice was widely considered a nod to China, where red symbolises good fortune and joy.
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The first lady welcomed Britain's Queen Elizabeth II and Prince Philip, the Duke of Edinburgh, to a reciprocal dinner in London, on May 25, 2011, in an elegant, off-the-shoulder black Ralph Lauren design. The evening look was accessorized with a side-part updo and a statement necklace.
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First lady Michelle Obama chose to wear Halston, one of the first American fashion house's to earn worldwide recognition, for the annual White House Correspondents' Dinner on April 30, 2011, in Washington. The chocolate-colored dress featured an empire waist and a low neckline. It was accented with a layered necklace piece and handful of bangles.
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She went for more of a flirter look with this sleeveless cocktail dress by Azzedine Alaia for a NATO summit dinner on April 3, 2009, in Baden-Baden, Germany. The black frock featured a ruffled skirt and was accessorized with matching patent pumps and simple jewlery.
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At the State Dinner honoring Mexican President Felipe Calderon and his wife Margarita Zavala on May 19, 2010, the first lady stepped out in a one-shoulder, electric blue gown by New York designer Peter Soronen.
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Mrs.Obama has worn several other designs by Peter Soronen since she has been in the White House, among them is this lavender, strapless pleated gown she wore for the Kennedy Center Honors on Dec. 6, 2009, in Washington.
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President Barack Obama and the first lady, in another Peter Soronen creation, at a White House black-tie dinner with the nation's governors on Feb. 22, 2009, in Washington. Mrs. Obama's pearl and crystal necklace was designed by Tom Binns.
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Mrs. Obama stepped out for the formal state dinner at Buckingham Palace, hosted by Queen Elizabeth II on May 24, 2011, in a white evening gown by Tom Ford. The dress featured a crisscross strapped neckline and ribbon details at the waist. Matching long gloves, dangling earrings and a shimmery evening clutch completed her look.
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At the 2010 White House Correspondents' Dinner, the first lady looked radiant in a red, jersey draped gown by Prabal Gurung. A straight, sleek bob and bold jewelry accented her look.
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Mrs. Obama donned an emerald empire-waist dress when she and President Obama hosted an evening celebration in honor of Stevie Wonder on Feb. 25, 2009, in the East Room of the White House. The dress was designed by Kai Milla, Wonder's wife.
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Mrs. Obama arrived at the Nobel Peace Prize banquet in Oslo, Dec. 10, 2009, in pale blue evening gown by one of her go-to designers, Azzedine Alaia.
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For a state dinner in New Delhi, India, on Nov. 8, 2010, with President Barack Obama, Indian President Pratibha Patil, and her husband Devisingh Patil, Mrs. Obama showed off her statuesque physique in a floor-length metallic skirt and a satin, bronze top by Rachel Roy.
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The first lady dazzled in a shimmery gold frock by Rodarte while chatting with Prince Albert II of Monaco during an International Olympic Committee reception in Copenhagen, Oct. 1, 2009.
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First lady Michelle Obama gave opening remarks at the Time 100 Gala, on May 5, 2009, in New York, dressed in a black gown by Michael Kors which was cinched with a Peter Soronen corset belt.
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The first lady first showed her support for young designers when she wore wore a white, one-shouldered, floor-length gown by then 26-year-old Jason Wu to President Obama's Inauguration Ball on Jan. 21, 2009.