Kate Mulleavy, one half of acclaimed Los Angeles fashion brand Rodarte, has had another long day. It's awards season, the international catwalk shows are in full swing, buyers have been in, and there's a trip to Hong Kong to prepare for. Her sister and design partner, Laura, has just come back from seeing European buyers in New York, and is off sick. It is a slightly chilly evening in downtown Los Angeles and Mulleavy relaxes into her seat on the patio a few floors down from the Rodarte design studio, and pulls out a cigarette. Although she's a co-founder of a line that is arguably one of the hottest and most closely-watched in contemporary fashion, Mulleavy seems nonchalant about all the hype. What is most important to her and her sister is the work itself, the creation of clothes that convey their organic, increasingly iconic and heartfelt sensibility, the result of a close eye, an even closer hand, and a tight-knit design studio of four. Today she is in her regular work gear of jeans, sneakers, T-shirt and roomy checked shirt, her conversation is serious and articulate, and her responses considered and thoughtful. 'It will be interesting to go to a place where I don't have any preconceived ideas,' she says of her and her sister's upcoming Hong Kong trip, their first. 'I have such a connection to the place where we grew up, and it's affected how we look at things. I have an idea of what Hong Kong will be like, but I'm excited to go and see if the reality matches that.' The Mulleavy siblings are in Hong Kong as guests of Joyce boutique, which carries their line. On Friday they will co-host a charity event for Unicef, with an exhibition and a silent auction. The sisters have donated four one-of-a-kind creations, inspired by actress Maggie Cheung Man-yuk and informed by some of her work, including In the Mood for Love and The Heroic Trio. These will be auctioned off, along with a Swarovski piece. A short film by Wing Shya, musical performances and a private dinner with Cheung and the sisters, will cap the event. The tie-up is especially serendipitous for another reason: Kate Mulleavy recalls one of her more memorable film classes at her alma mater, University of California Berkeley, that focused on the work of Wong Kar-wai. Both the sisters went to the same college and graduated with liberal arts degrees in the same year (Kate is older by about 18 months); Kate studied art history with a focus on the 19th and 20th centuries, Laura literature and the modern novel. They had no professional design training, but Mulleavy says that she 'grew up sketching clothes my whole life'. 'It was like a nervous tic,' she says now. 'It was a compulsion.' Both she and her sister wanted to work in fashion and have their own line, but concedes that 'we didn't know what we were doing'. 'Our first year out of school, we watched horror films all day long,' she recalls. Surprisingly, their parents - their father is a botanist and mushroom expert, their mother an artist - were fine with their daughters' decisions to spend hours a day at the family home in Pasadena, immersed in scream flicks, while they figured things out. 'After that year, we just jumped in,' says Mulleavy. 'We said, 'either we do it now, or we'll never do it.'' It helped that both girls had been sewing since they were young, having grown up wearing clothes made by their mother. By 2005 the sisters had compiled a capsule collection of 10 hand-finished pieces, which they carted off to New York. They knocked on a few doors, made a few calls - but the clothes spoke for themselves. Within days of their arrival, they had made the cover of Women's Wear Daily, and a few weeks thereafter landed a meeting with Vogue's Anna Wintour. 'We had never even been to New York before that first trip,' says Mulleavy. 'We didn't think in a million years that we would end up on a WWD cover. But we had a belief that we were meant to do this and we had the creative desire. Things did happen quickly for us, but we were very dedicated, and that type of dedication comes when you love something.' They showed their first fully fledged collection in New York that same year and won the Ecco Domani Fashion Foundation Award. Their debut line scored orders from Bergdorf Goodman, Colette and Barneys. There were nominations from the Council of Fashion Designers of America (CDFA), with the girls finally taking home the award for Emerging Womenswear Designer in June 2008 and, last year, the top prize of Womenswear Designer of the year. A Rodarte gown is in the permanent collection at the Costume Institute of the Metropolitan Museum of Art, and last month, the brand had its first museum exhibition at the Cooper-Hewitt in New York. Throughout, Mulleavy says that she and her sister have been directed by what she calls 'a gut feeling'. 'Things come from our personal memories, and an interest in culture and the arts,' she says. 'The type of designers that Laura and I must be, what makes us through season to season, is that we want to take people to different places. As designers who work in a certain vernacular, it's how we feel about a collection. We want people to have an emotional reaction and response to the clothes.' In addition to the critical acclaim, abundant retailer support and awards, Rodarte has another, undeniably important, endorsement - of the celebrity kind. Actresses known for their natural style - Cate Blanchett, Keira Knightley - have been seen in Rodarte creations. When First Lady Michelle Obama met Queen Rania of Jordan last year, she wore a pleated, taupe Rodarte dress. At their core, despite the intimate workmanship and esoteric references, the clothes are the last word in wearability. The designers take their influences wherever they find them. For the autumn/winter 2010 line, shown in New York in February, they were inspired by a trip to El Paso and the border towns of Mexico. The collection is rooted in the idea of these towns being 'transient spaces', says Mulleavy. That led to the idea of styling their models like sleepwalkers, dressed in dreamy, translucent colours and fabrics. There are also Mexican influences, seen in the draped floral dresses. 'Part of our family comes from Mexico,' she says. 'We grew up in that heritage, and it's an aesthetic we understand.' They spent some of their early years in Santa Cruz, south of San Francisco, where they were surrounded by 'punks and surfers, a huge surf and skate culture and hippies.' They devoured fashion magazines, and watched films for the costumes. The street culture around them was rooted in a counter-culture, and from that environment the Mulleavy sisters absorbed influences that serve them to this day: their love of draping comes from the saffron robes of the devotees of Hare Krishna. And there is always something unexpected. A diaphanous floral draped gown was shown with a cosy shrug, hand-fringed skirts were paired with pieces inspired by macrame and crochet. Everything is artisanal with a couture sensibility and none of the pretension generally of lines accorded that description. The work is inventive, deeply personal and profoundly thought through. Mulleavy says they are still learning, refining the technical aspects of their work as they go, although you wouldn't know it to look at the faultless craftsmanship. In one collection, a series of intricate leather jackets was the result of a dream. 'There is no handbook on how to do leather like that,' she says. 'We learn a lot from the people we work with and they learn our hand. Our knowledge grows season to season.'