He showed an interest in fashion from an early age, critiquing his mother's clothes and sketching his own designs at school. Taunted by fellow students for his interests, the late maestro got into the habit of reassuring himself with the words: "One day you will be famous". He was right, of course. But the "Little Prince" of Paris fashion found fame much sooner than even he expected.By the time he was 18 he was working with Christian Dior in Paris. And such was the legendary's designer's faith in his young assistant that when, four years later in 1957, he took a holiday, he did so with a blithe heart, informing his sales director: "I am going away without any worries. I am leaving you with Yves". While on vacation Dior suffered a fatal heart attack, and suddenly the 21-year-old found himself at the head of the venerable Dior empire. His debut collection, which included the now famed trapeze dress, was well received and drove sales up by 35 per cent. He was drafted into the military two years later, however, and lost his prestigious post.After being discharged from the Armed Forces, Yves and his partner Pierre Berge set up the designer's own label. And Yves became the toast of haute couture and European society, befriending everyone from Marlene Dietrich to the Duchess of Windsor. Ever the innovator, he introduced a series of firsts into female fashion, including the trench coat, the Mondrian print dress and trouser suits. In 1996 he was the mastermind behind arguably the most famous classic tuxedo suit for women, 'Le Smoking', and was also the first designer to use black models in his runway shows.French actress Catherine Deneuve, one of the designer's muses, once described the fashion maestro as "charming, adorable, funny". But to his partner Pierre, Yves was a perfectionist who was "born with a nervous breakdown". A sensitive soul plagued by depression, the creative talent behind the fashion house was at one point committed to a mental institution. His survival owed much to Pierre's support, although he remained troubled for years despite turning out some of his best-reviewed collections of the era.In 1993 Pierre brokered a deal in which the Yves Saint Laurent conglomerate was sold to France's state-owned pharmaceutical giant Elf Sanofi. He and the designer each pocketed a stunning $72 million. An agreement with Gucci led to wunderkind Tom Ford taking over YSL ready-to-wear, allowing Yves to focus on what he did so very well haute couture. The designer was increasingly plagued by ill health, however, and in 2002 he announced he was quitting fashion, bringing a 40-year career to close.He had little time to enjoy his retirement at his Morrocan property in Marrakech, though. On June 1, 2008, after suffering from brain cancer for a year, he passed away at his home in Paris.