Pierre Berg??, the business partner of the lateYves Saint Laurent, has died aged 86 at his home inSaint-R??my-de-Provence, southern France after a long illness.

WhileBerg?? may not have put his name to the Yves Saint Laurent empire, he was the maison"s co-founder and the business mind behind its success.Berg?? and Saint Laurent went into business together in 1960 after the designer had left Dior following a series of controversial collections.

Saint Laurent"s eponymous label became a renegadepresence in the fashion industry thanks to a series of bold design offerings from 1966"s Le Smokingto the Mondrian-influenced collection of 1965.

"You can"t separate them out, but his male suits that he dressed women in were revolutionary,???Berg?? told The Telegraph last year as he launched two museums dedicated to Saint Laurent"s legacy."It is the one piece of clothing that is 100 per cent masculine, so to get a woman to wear it was quite something.At the same time, if a woman is to wear a masculine piece of clothing, she has to develop her femininity and her weapons of seduction.???

Berg?? remained dedicated to the business until his departure in 1999 and has been a fierce protector of the designer"s memory since his death in 2008- the couple were joined in a civil union shortly before Saint Laurent succumbed to cancer.

"We are the only ones to have such a collection; neither Balenciaga, nor Dior nor Chanel can claim this, because they didn"t keep the original outfits, only the customers" models," Berg?? said of the enormous archive which he had meticulously preserved of Saint Laurent"s work, said to contain 5,000 Haute Couture garments and 15,000 accessories."During each collection, he"d say, "that will go in the museum",???Berg?? remembered."He was aware, and he was right, that he was the last of the great couturiers."

In recent years, the art collector and gay rights campaigner, has been outspoken on the state of the fashion industry and the direction of the Yves Saint Laurent label today.Despite widespread controversy about the designer Hedi Slimane"s overhaul of the house in 2012, Berg?? was unafraid to praise his collections."I adored it; it"s exactly what needed to be done," Berg?? said of Slimane"s debut."It???s very moving for me, because it???s the spirit of Saint Laurent, but revisited with Hedi???s enormous talent."

The rest of theindustry, however, was not met with such high praise."Today, the fashion houses supposedly continue to turn out haute couture but they don"t have customers, because I don"t call Russian prostitutes customers," he said in last year"s interview with The Telegraph."They continue to offer it in the belief it will sell ties and perfume - that"s their right but I don"t believe it and think it is condemned to die out.???

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