At Prada USA, de Boni succeeds Constance Darrow, who held the post for seven years and helped the company expand its network of boutiques to cities such as Las Vegas and Aspen, Colo., in addition to its large-scale Epicenter stores in New York and Beverly Hills. (Darrow recently resurfaced at Vera Wang as president of creative direction.)

Also beefing up its American team, Prada named Kirsten Peters as executive vice president of wholesale with responsibility over the Prada brand's ready-to-wear, handbags and accessories divisions, excluding footwear. Previously, Peters had a long career at Giorgio Armani and has also worked for brands including Joseph Abboud, Escada and Valentino.

Despite the long-standing management vacancy in the U.S., Prada Group's business has soared ahead.

Last month, in disclosing a 65.8 percent jump in 2007 earnings, Prada highlighted a 10.8 percent increase in sales in North America — its second biggest market behind Europe — despite the signs of an economic downturn in the second half of last year and the strong euro.

"This performance is even more significant considering the best results were achieved in the second half of the year," Prada noted at the time. The Italian group, which owns the Prada, Miu Miu, Car Shoe and Church's brands, said overall sales for the period increased 14.1 percent to 1.66 billion euros, or $2.27 billion.