25 most powerful people in business

Chairman and CEO, LVMH

Arnault is best known for turning LVMH, already a luxury-goods giant when he won control in 1989, into a global empire through acquisitions, savvy marketing, and bold design. The $19 billion company, in which he's also controlling shareholder, boasts more than 60 brands, including the eponymous Louis Vuitton, as well as Marc Jacobs, Dom Pérignon, and beauty chain Sephora.

But Arnault's influence reaches far beyond couture and champagne. He's a close friend of French President Nicolas Sarkozy; a newspaper baron who's currently selling one business daily, La Tribune, and acquiring its rival, Les Echos; and a powerful arts patron: Arnault got the go-ahead last fall to build a center for LVMH's art foundation in the Bois de Boulogne.

This spring Arnault, 58, who is France's richest man, turned activist shareholder when his holding company paired with private equity firm Colony Capital to buy a 9% stake in Carrefour, the world's second-largest retailer. Arnault made his mark felt fast: In August, Carrefour announced plans for a $6 billion stock buyback program. --Eugenia Levenson