In the last five years, traditional fashion houses have reinvented themselves by hiring hip young designers Tom Ford at Gucci, John Galliano at Dior, Marc Jacobs at Louis Vuitton and their accessories, in turn, have acquired a new cachet. In January 1997, after Mr. Galliano showed his first Dior collection, sales of the Lady Dior catsuits quilted and adorned with the house's jangling, gilt letters increased 40 percent.