She's lovely, and I'm terribly disappointed. She dresses fashionable and fabulous London society girls and has a boutique on the famously posh Pont St, so admittedly I was expecting someone a bit aloof, a successful New Zealand 20-something who not-too-secretly thinks that home is a hicktown. A Sloane Ranger. A Chelsea princess straight from the pages of Tatler. But no, when I meet designer Emilia Wickstead at her atelier one rainy London afternoon, she is lovely.

Wickstead was born in Auckland, and lived here until she was 14, when she followed her mother, Angela, to Milan. Those formative years in the city that lives for fashion were crucial to her development as a designer.

As she tells me over a cup of tea (me) and a diet Coke (her) in the private salon space downstairs at her studio, she had no dreams of being a fashion designer while living in New Zealand - she wanted to study art history.

But living in Milan, where the women dress up and the men often dress up even more, would certainly influence a young girl - as would a mother who was a successful made-to-measure designer.

The 26-year-old moved to London to study fashion design and marketing at London's Central Saint Martins (you know the graduates: Alexander McQueen, John Galliano, Stella McCartney, Phoebe Philo, etc), before moving to New York where she spent time working at various fashion houses and at US Vogue as an "assistant to Andre Leon Talley's assistant".

Her international background probably contributes to her sense of maturity; she has that determination and confidence that successful female fashion designers often exude - she says that when she graduated she knew it was "part of my character to launch something of my own".

It certainly took confidence to launch a solely made-to-measure label in 2008, a concept that seems almost old-fashioned and quaint. But it worked: she quickly developed a following in certain London circles, featured in UK Vogue and Tatler and was described by Italian Vogue's website as a "posh young talent".

Her clothes are posh, often described using that terrible fashion phrase "classic with a twist". I would describe them using more terrible fashion phrases: simple, elegant, sophisticated, feminine - much like Wickstead herself.

Her store and atelier reflect this attitude too - a light, airy space, all white walls and square sofas, with a private salon space downstairs and the recently launched ready-to-wear pieces showcased in the store upstairs. After our interview Wickstead takes me on a "tour" of the downstairs atelier, where her small team produce everything in-house.

There's the main area where she hosts clients and works on their made-to-measure garments (and holds private salon-style fashion shows at the beginning of each season, much like the old couture houses used to do).

An array of fabrics are displayed in a giant cupboard (clients can choose from 25 colours to one fabric, and everything is made to fit). There are Mario Testino originals framed and hung on the wall, acquired from Wickstead's time at US Vogue, and piles of fashion books neatly arranged on a large glass desk.

A book about Grace Kelly's style sits at the top of one pile, someone who would, if she were still alive today, perfectly suit Wickstead's designs. The book is part of the popular V&A exhibition celebrating Kelly's style; an exhibition so popular that it was sold out on the day Wickstead went.

Behind a door is the workroom area of the salon; a cutting room, wrapping room and a room where four or five women work to create the garments. Racks and racks of clothes currently in production are lined up outside this space and hint at the success of the label - a success possibly helped by Wickstead's recent very important client, Samantha Cameron.

The wife of British Prime Minister David Cameron, and former creative director of high-end luxury goods brand Smythson, has been wearing Wickstead's designs a lot lately. Pieces, in fact, that are part of a small capsule range which the designer put together especially for her - a black and white dress with a sweetheart neckline to welcome French First Lady Carla Bruni to 10 Downing St, a purple belted dress to wear whens her husband made his first speech as Prime Minister, a ruched bright purple shift dress to vote in.

Like most things in fashion, the chance to dress Britain's First Lady came about through friends.

In New York Wickstead befriended Lohralee Stutz, who last year married Cameron's half-brother Will Astor (Wickstead was a bridesmaid at the wedding that was reportedly dubbed the society wedding of the year by Tatler). Wickstead has also known Cameron's stylist for years.

The reaction to having such a high-profile model for her designs has been, unsurprisingly, huge.

"It was on the cover of about 15 newspapers and in every magazine," explains Wickstead.

But she seems happier about the fact that Cameron, and by extension herself, is being celebrated for changing the way political figures dress when pregnant.

"They don't have to go dowdy, they can show off their bump and celebrate it."

Wickstead tries to come home - and she does call New Zealand home - at least once a year, although business has been getting in the way of that recently. She lives across the street from her store with her boyfriend and business partner, Daniel, and says that she currently lives and sleeps work - but loves her London life.

"It's not New Zealand at all, but I think it's the closest thing. Living in Milan was not difficult, but it's another world. Here in London you can go for picnics and have a barbecue, you can go to a park and wear bare feet, much like New Zealand. But there's just so much buzz going on; you can be inspired by anything and everything. There's always something to do. Always."

EMILIA'S LONDON
Dean Street Townhouse

I love this restaurant for dinner. They have the most incredible champagne glasses - as the waiters say, in the exact shape and size as the breast of the late Marie Antoinette. These glasses make drinking champagne all the more exciting.

Cecconi's

A favourite for lunch and dinner, as the atmosphere is always buzzing. The people who lunch there are always magazine and fashion professionals, which is an extremely exciting atmosphere to be eating in.

Ottolenghi

Great for take-out lunches and small treats - I love their chocolate cake, eggplant salad and beef fillet. The decor is all white and clean and the incredible food display simply speaks for itself.

Hyde Park

So close to home, and where you can find me on a sunny afternoon.

The Connaught

I love going to the bar there for drinks - it is truly New York-style fabulous and a great people-watch. The decor is slick and sophisticated. One of a kind in London.