A favorite of the fashion world, known for his low-key personal style, affinity for the contemporary art world, and talent, Mr. Simons originally made his name with an eponymous men’s wear line, but achieved broader fame thanks to his ability to breathe new life into troubled brands.
He took on Jil Sander after the brand’s founder had come and gone twice, later moving on to Christian Dior following the ouster of John Galliano. He left Dior in 2015 after three years, frustrated that his creative oversight was limited to the women’s runway collections.
It was a situation Mr. Simons ensured would not be replicated at Klein, where he was given authority over all the brand’s product categories, including the runway lines, jeans, underwear and homewares, as well as advertising and store design. Previously, these responsibilities had been shared by a troika of designers: Francisco Costa for women’s wear, Italo Zucchelli for men’s wear and Kevin Corrigan for jeans and underwear.
Though commercially the brand was a success, it had not been a driver of fashion since the sale of the company in 2002. Indeed, the runway collections were so minor, they were classified as a marketing expense on the brand’s balance sheet, according to Tom Murry, the former chief executive.
Mr. Simons was supposed to change all that.
In handing the keys to the Klein kingdom to Mr. Simons, Steve Shiffman, chief executive of the brand, was following the model popularized by Gucci. The wholesale reinvention of Gucci under Alessandro Michele, the creative director, has been the biggest success story of the current fashion industry.
Also influential has been Hedi Slimane, a designer and the former creative director for Yves Saint Laurent and current creative chief of Celine. Mr. Slimane, who is famous for insisting on control over every aspect of a brand down to designing the fittings in the stores, sent Saint Laurent sales soaring, and currently has everyone watching Celine. Along with Mr. Michele, his success set trends not just on the runway but in the C-suite as well, and paved the way for the deal between Mr. Simons and Calvin Klein.