Collins, Amy Fine. "When Hubert Met Audrey." Vanity Fair December 1995: 278-295.
According to this Vanity Fair feature, lifelong friends Audrey Hepburn and French fashion designer Hubert de Givenchy met during the making of Sabrina. Hepburn, who would later favor Givenchy as her signature brand in both her movies and her real life, was relatively unknown in 1953 when she flew to Paris to enlist the then up-and-coming Givenchy to design her wardrobe for Sabrina. Like her character at the beginning of the film, Hepburn was not used to wearing high fashion clothing, but both she and Sabrina would become sophisticates. Though Edith Head was credited as the film's costume designer and even took home an Oscar for her work, it was Givenchy, in collaboration with Hepburn, who created the film's most iconic looks.
Collins points to the "jazzy suit" Hepburn's Sabrina wears at the train station when William Holden's David Larrabee first notices her, the floral white ball gown that essentially serves as Sabrina's coming out outfit, and the black cocktail dress that "spawned a thousand knockoffs." These couture looks featured different necklines and cuts than were typical at the time, and were tailored to emphasize Hepburn's slight frame. When Hepburn doubted her acting abilities, Givenchy's clothes provided her with the solace that she at least looked the part.
Collins writes that the clothes also went on to inform plot details of the film. Inspired by Hepburn's sophistication in the Givenchy suit, screenplay writer Ernest Lehman changed the script to make David Larrabee unaware of Sabrina's identity when he picks her up at the train station. Later, in the ball scene, Sabrina's simple but elegant dress distinguished her character. Lehman said of the film's wardrobe, "[The clothes] were extremely helpful to the character, the mood, the movie. They made the transformation believable."
Hepburn's star--and salary--shot up after the release and success of Sabrina. In addition to their impact on the film's success, Collins believes Givenchy's designs for Sabrina shaped Hepburn's public persona. The actress added to this effect by wearing clothes from the movie while promoting it in Europe. Hepburn-eqsue designs also continue to influence current fashion. Collins' article is an interesting, though not scholarly, take on the influence fashion can have in the success of a film, or in Audrey Hepburn's case, an entire personal image.