Valentino, one of Italy's most famous designers, has secured a spot in the vast wardrobe of Qatar's Royal family.
The private-equity house Permira has sold Valentino to Qatar's investment vehicle Mayhoola in a €700m (£553m) deal.
Valentino will join Qatar's other luxury investments, including the department store Harrods, a 1 per cent stake in the French luxury goods group LVMH, and the 5.2 per cent stake in US jewellery business Tiffany – owned by Qatar's Investment Authority.
Founded by the designer Valentino Garavani, the Italian brand was bought by Permira in partnership with the Italian Marzotto family in 2007. In the same deal, Permira bought German brand Hugo Boss, which it still owns.
Stefano Sassi, the chief executive of Valentino, said: "We are delighted with this development. During the past few years, despite swings in the luxury markets, the company has operated with great intensity. This effort should drive a 60 per cent increase in revenues from 2009 to 2012."
Valentino reported that sales for the first half of 2012 are up 23 per cent on the same period last year.
Fellow Italian fashion house Prada launched an IPO in Hong Kong last year, while Salvatore Ferragamo floated on the Milan stock exchange.