Fashionistas around the world are chomping at the bit to learn which Hollywood leading lady will wear what designer as the countdown to the 2012 Oscars ticks closer.  

Paris Haute Couture Fashion Week wrapped up Wednesday after three days of dazzling displays by designers like Versace, Armani Privé, Christian Dior, Chanel and Elie Saab. The stunning myriad offerings of Spring/Summer 2012 haute couture brought brilliance to even the rainiest days in Paris. Unleashed imaginations displayed fantastical collections rife with whimsy and decadence. Bright hues, architectural shapes, superfluous ornamentation and tons of glitter floated down the runways.

Paris Fashion Week only made the countdown to the 2012 Oscars that much more exciting. Who will wear one of Karl Lagerfeld's edgy stewardess frocks? Who will make the bold move of zipping into one of Jean Paul Gauliter's Amy Winehouse-inspired dresses?  

The Oscars is quite possibly the most important night for a designer. Aside from showing a new collection, the Academy Awards show puts the designer front and center as his or her piece dons the body of a hot Hollywood actress. There is no better exposure.

If you want a custom gown sketched by a designer with beading and embroidery, that can take many weeks to prepare, Marilyn Heston, head of MHA, an Los Angeles-based international company that pairs celebrities with designers and luxury brands, told The Hollywood Reporter.

It's not an overnight deal to get a spectacular Oscar dress. Generally, these tailor-made dresses are only offered to nominees and presenters for the Globes and the Oscars. If a designer spends all that time and money on a gown, they want to make sure that it will end up in Vogue or Women's Wear Daily. This is not an artistic endeavor. The only reason a global designer is dressing an actress is to gain exposure that will raise awareness and increase sales.

The Hollywood Reporter scored all the details on who is styling whom for the 2012 Oscars. Since the nominations went out on Jan. 24, stylists' phones have been ringing off the hook with requests for the 10 leading ladies who clenched the Best Actress and Best Supporting Actress nominations.

Meryl Streep: The Best Actress nominee for her role as British Prime Minister Margaret Thatcher in The Iron Lady, is working with stylist Zoe Buck.

Viola Davis: Nominated for Best Actress in a Leading Role for her part in The Help, Viola Davis will work with longtime stylist Elizabeth Stewart of The Wall Group. Stewart was a fashion editor for The New York Times Magazine and has worked with the likes of Cate Blanchett and Jennifer Lawrence.

Jessica Chastain: The fast-rising newcomer was nominated for her supporting role in The Help. She is also working with Elizabeth Stewart.

Michelle Williams: My Week with Marilyn star Williams worked with Elizabeth Stewart for the 2011 Oscars. Stewart styled Williams in Chanel couture. This season, Williams is working with Kate Young, a New York stylist and former Vogue editor who was behind Natalie Portman's creative wardrobe last Oscars season when the Black Swan actress was pregnant.

Rooney Mara: The Girl with the Dragon Tattoo star, nominated for Best Actress for the 2012 Oscars, is working with under-the-radar stylist Ryan Hastings. Hastings, a former fashion editor, has worked with Robert Pattinson and Mia Wasikowska.

Glenn Close: Close will work with New York stylist Chuck Thomas. Thomas formerly worked for Giorgio Armani in the U.S. Close was nominated as Best Actress in a Leading Role for Albert Nobbs.

Bérénice Bejo: French actress and star of The Artist Bérénice Bejo is not working with a stylist, as she prefers to make her own wardrobe choices. However, THR cites that Bejo has a longstanding relationship with the Elie Saab team in Paris.

Melissa McCarthy: Funny gal Melissa McCarthy, nominated for Bridesmaids, is working with Simon Tuke, costume designer for Everybody Loves Raymond and McCarthy's show Mike & Molly.

Octavia Spencer: Nominated for Best Supporting Actress for her role in The Help, Octavia Spencer will work with sister stylists Wendi and Nicole Ferreira to pick her red carpet ensemble.

Janet McTeer: The British actress, who scored a Best Supporting Actress nod for Albert Nobbs, will be handling her own wardrobe.

Here are some Oscars 2012 gown predictions from Paris Haute Couture Fashion Week for the top 10 Hollywood leading ladies.