Such an aggressive strategy is not without its dangers. Fashion critics and magazine editors, who have so profound an impact on fashion companies that they are virtually part of the manufacturing chain, have their doubts about how long Gucci can ride on its reputation. While some critics have politely applauded Giannini’s designs, they have also taken potshots at her low profile in the industry and damned her clothes with faint praise for their “wearability,” a mortal wound in high-fashion circles. The catch-22 of having an easygoing designer willing to help you do what it takes to go global, versus a superstar control freak, is that in a few years, there could be little left to control.

“Their goodwill, their cachet is trickling away,” says David Wolfe of the Doneger Group, an independent fashion consultancy that predicts trends for retailers. “It’s a little like Versace after Gianni’s death. Frida hasn’t been able to reestablish consistency. They are going to eventually come to a breaking point.”

Pinault seems acutely aware of the delicate balance. When he is told that Guy Trebay, an influential critic for the New York Times, recently wrote that ­Giannini is more of a stylist than a designer, Pinault looks as though he has been hit in the gut with one of Gucci’s massive logoed totes. “That’s terrible,” he gasps, leaning back in his chair. “I would hate for her to hear that. I think she’s very, very talented. But really, I don’t think that is the future, that opinion of her.”

 
It's unusually mild for Paris in January, but Valérie Hermann, the C.E.O. of YSL, is too wound up to enjoy the weather. The men’s show for her money-losing label is a week away, and today is casting day; the upper floors of the YSL atelier, in a mansion on Avenue George V, are thick with grungy, beautiful boys and rolling racks of clothing. The women’s show will follow in about a month. And, as if that weren’t enough pressure, Pinault is now sitting with Hermann’s top aide at a conference table in a black-and-white salon.

Pinault doesn’t visit often—his brand C.E.O.’s report directly to Polet—but he does tend to watch YSL a bit more closely than the other labels. Hermann was his business school classmate, and YSL holds a special place in his heart. Along with Hermès, Dior, and Chanel, the brand is virtually considered a national treasure. But what’s perhaps most important is that YSL—for which his father paid what analysts considered a far-too-rich $1 billion—is deeply, famously in the red. Saint Laurent himself, brilliant but temperamental, had let the label founder in the last few years he owned it.

The YSL line is now designed by Stefano Pilati, a 41-year-old Italian who worked under Ford. Last year, it brought in $260 million; breakeven is $400 million. Pinault will not name a year, much less a quarter, when he expects to reach that goal. Pilati, tattooed from wrist to shoulder beneath his cashmere sweater and ascot, has not had an easy glide down the runway. His first collections were savaged for their incoherence and lack of fresh ideas. But recently the brand has gained some traction. YSL’s sales are up nearly 20 percent since last year, boosted by an equivalent increase in the company’s advertising and promotional budgets. Still, the brand has a long way to go, and Pinault is well aware that these are the best of times. He knows YSL will have to pull its weight even when it becomes a lot harder to sell $4,900 ostrich handbags and $2,900 pearl-adorned heels.

“We have some really great numbers to show you,” Hermann tells Pinault, as her aide fires up a PowerPoint presentation. But what flashes up on the screen are not sales figures. Instead, these data chart the increase in paparazzi shots of celebrities—Nicole Kidman, Jennifer Lopez, Sienna Miller—carrying YSL handbags that were “placed” with them for free. Even at the most successful fashion houses, accessories—handbags, scarves, wallets, sunglasses, and perfume—account for as much as 80 percent of revenue, and such photos can elevate a new product to hot-bag status.