“Oh God, maybe I should have dressed up for this,” says New York fashion designer Tory Burch, noticing her bare feet curled up beneath her while sitting on a yellow chair in her expansive library. On the floor are a pair of second-hand, chocolate-brown Manolos that belong to her 20-year-old stepdaughter, Izzie. But Burch isn’t the type to navel-gaze for long about her appearance. Considered one of Manhattan’s best-dressed women and the leading lady of NYC young society, she is still looking her effortlessly chic self: manicured toes (clear nail polish), form-fitting jeans and a black cashmere sweater (all from her own label, Tory Burch). Oh, and a dollop of mesmerising accessorising: an hors d’oeuvre-size, Asscher-cut diamond ring and big diamond earrings set in antique silver.

The ever-confident Burch couldn’t care less what prying eyes think of her (which may account for the tuft of stuffing sticking out of the red sofa in her super-stylish, 9,000sq ft apartment in one of Manhattan’s premier hotels). In the past two years, she has built one of the US’s hottest fashion labels. And it’s just arrived in the UK, with a range available at Harvey Nichols in Leeds and London.

Burch hopes that London ladies will love the bohemian femininity of her phenomenally successful clothing line. Burch’s affordable, well-cut clothes “give you a designer feel”, while their versatility prompted actress Reese Witherspoon to enthuse: “Her clothes go from day into evening – they’re great for moms who don’t have time to change.” Not to mention working women. “The label is definitely for busy women on the go,” Burch says. “I wanted to do something that was different. Traditional designer brands are outrageously expensive. I studied what I thought was missing in the market: a lifestyle concept that was luxury in spirit, but well-priced.”

Manhattan’s new style arbiter isn’t shy about taking on a massive mission. Most designers spend years establishing their names and eventually expand into accessories. But Burch, 38, introduced an entire lifestyle brand: there were her bold colours (her favourite hue is orange, but she uses touches of French blue, teal or green), geometrically patterned silk blouses, and her trademark velvet and corduroy slacks and short-cropped jackets, with ubiquitous border. But, when she opened her first boutique in Downtown Manhattan, she also offered everything from jewellery to candles. Burch also ensured that her sizing doesn’t vary from season to season, allowing customers to reorder from her website (www.toryburch.com).

Take her boho, Talitha Getty-esque tunic, for example. Its flattering shape has become a Burch staple (many believe that Burch propelled the tunic’s recent popularity), and suits all body-types, whether it be the slim, 5ft 4in Burch, or the more voluptuous Mariah Carey. Unknown to Burch, the chanteuse wore her ivory linen tunic with rhinestones as a miniskirt in the video for last year’s hit, We Belong Together. It was a stroke of luck, but when it comes to exposure, it was nothing compared to the endorsement of Oprah Winfrey. Last spring, she introduced Burch as the Next Big Thing on her talk show. Burch’s website received eight million hits. “It changed our business overnight,” says Burch, who has since opened boutiques in Los Angeles, Atlanta and Dallas, and soon in Greenwich, Connecticut (she is also present in America’s top department stores). “I think Oprah loved the idea of a female entrepreneur taking the chance on a lifestyle concept with some easy, no-brainer clothes that were well-priced.”

Burch concedes that she undertook a huge “gamble” when she embarked on her new venture. Manhattan’s most photographed social belle was a natural target: she could have been pummelled by the press and ridiculed by her peers. “I could have been laughed at,” Burch admits. “When I first started, a lot of sceptical people were rolling their eyes. I think they expected a T-shirt line.”

But the self-described “farm girl”, who hails from an affluent area outside Philadelphia, had been hatching her plans for years. After returning from black-tie soirées, she stayed up into the night to ring Chinese manufacturers and pitch them her concept. “I don’t think a lot of people, including myself, realised that I was such a business woman,” Burch says. Of course, it didn’t hurt that since graduating from the University of Pennsylvania in 1988 and settling in New York, she had already worked in stints for Harpers Bazaar, Ralph Lauren, Vera Wang and Narciso Rodriguez at Loewe. She also received invaluable financial advice and seed money from her second husband, Chris Burch, a successful venture capitalist. (Her first marriage, at the age of 24, ended after six months. “It was hardly a marriage,” says Burch, who is loath to discuss it. “It was like an extended date.”) After marrying Chris in 1996, Burch inherited three young stepdaughters. She then gave birth to twins, now aged eight, and also has a five-year-old.

Burch juggles a brood of children while maintaining three residences – in addition to their New York apartment, the Burches own a modern manse in Southampton, Long Island, and a home in the Pennsylvania countryside. Now she’s added a booming clothing brand (it has grown ten-fold since its inception) to the “to-do” lists in her hefty diary. She may have a smooth-running staff (at home and at the office) and a driver to pop her around Manhattan in her Cadillac Escalade SUV, but she is the first to admit that “something had to give”. Though she is still active in the city’s charities, she has scaled back her nocturnal life. Burch loves nothing more than skinning rattlesnakes with her boys on holidays in Montana. “Family comes first,” the sleep-deprived Burch insists. “I work my tail off, because it’s important to show my children that a working mother can be independent. But if I can help women get dressed more efficiently, then I’m even more thrilled.”

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