Anna Wintour has been the undisputed queen of the $350 billion fashion industry since taking over the editorship of American Vogue in 1988.

She is the cover star - in a shoot by Mario Testino - of WSJ Magazine , the Wall Street Journal's glossy weekend magazine, which goes on sale tomorrow in the US. The accompanying story seeks to explain why Wintour, after all these years, is still the most powerful figure in fashion.

R. J. Cutler, the producer of "The September Issue", tells the magazine: "You can make a film in Hollywood without Steven Spielberg's blessing, and you can publish software without Bill Gates's blessing, but you can't succeed in fashion without Anna's blessing."

Wintour transcends the boundaries of what a fashion magazine editor does. She has, for example, urged the French government to fund young designers; organised an annual night of shopping called "Fashion's Night Out" to help New York's struggling retailers through the recession; and vigorously promoted young talent - like Marc Jacobs - to the bosses of the luxury conglomerates. Jacobs took the reins at LVMH's Louis Vuitton in 1997 largely because of Wintour's tutelage.

Of finding new talent to feature in the magazine - Sean "Puff Daddy" Combs and LeBron James, the basketball star, have been a few eyebrow-raising inclusions over the years - she says: "There are people who are like beacons, and I'm in the fortunate position that I can meet such people.