Marion Cotillard has been revealed as guest of John Galliano (Dior) for the upcoming prestigious Costume Institute Gala in New York, which takes place next Monday, May 4.

The Model as Muse: Embodying Fashion, the spring 2009 exhibition organized by The Costume Institute of The Metropolitan Museum of Art, will explore the reciprocal relationship between high fashion and evolving ideals of beauty, focusing on iconic fashion models in the latter half of the 20th century and their roles in projecting, and sometimes inspiring, the fashion of their respective eras. The exhibition will be on view at the Metropolitan from May 6 through August 9, 2009.

To celebrate the opening of the exhibition, the Museum’s Costume Institute Gala Benefit will take place on Monday, May 4, 2009. Marc Jacobs will serve as Honorary Chair of the Gala. Co-Chairs are Kate Moss; Justin Timberlake; and Anna Wintour, Editor-in-Chief of Vogue. This fundraising event is The Costume Institute’s main source of annual funding for exhibitions, acquisitions, and capital improvements.

Designers in the exhibition will include Giorgio Armani, Cristóbal Balenciaga, Pierre Cardin, Karl Lagerfeld for Chanel, André Courrèges, Christian Dior, John Galliano for Christian Dior, Rudi Gernreich, Halston, Marc Jacobs for Perry Ellis, Charles James, Donna Karan, Calvin Klein, Helmut Lang, Ralph Lauren, Prada, Paco Rabanne, Yves Saint Laurent, Giorgio di Sant’Angelo, and Gianni Versace.

Traditionally, everyone’s wearing gorgeous and spectacular dresses to the Costume Institute Gala. I can’t wait to see Marion’s choice!

Sources: Fashion Week Daily, MetMueseum