Richard Nicoll is almost too serious. He salts this interview with words such as ''dignity'', ''modernity'', ''function'' and ''flattery'', which are odd from a designer pitching to the chainstore 16 to 24-year-old girl/woman market in which skirts up to here and necklines down to there are as common as ponytails. ''My designs are about sensuality and a sense of modernity, not overt sexuality,'' Nicoll says. ''I'm a classicist.''

Sportsgirl commissioned the London-based Australian expat to design a nine-piece capsule collection, the latest in its series of collaborations with independents that help diffuse its ''mass fashion'' identity.  Nicoll's group - clean-cut separates, finely striped and checked with whimsical heart motifs - went on sale online this week and will be racked in stores on Monday.

Response was instant, Sportsgirl says, and ''overwhelming''. It was also probably a huge relief because, despite his credibility in London and Paris and widespread belief he is on the brink of global greatness, Nicoll is not well known outside fashion circles here.

In London his eponymous label is renowned for its technical and pared-back brilliance. He was also recently appointed creative director of Fred Perry's top womenswear line, has consulted to Louis Vuitton, produces an annual capsule range for Topshop and until earlier this month, designed for venerable Paris fashion house Cerruti. (Its new Chinese owners specialise in menswear, so opted to drop the women's line.)

It was also Nicoll's mixed heritage - he has New Zealand parents and passport, was born in London, raised in Perth, moved back to London at 17 where he graduated with a master's degree from prestigious Central St Martins College - usually bundled as ''Australian expat'' by local media, that swung his Sportsgirl commission. ''Our most fashion-forward collaboration to date,'' says its blurb.

The collaboration might also be the store's most subtle and complex. ''There's a lightness and elegance and dignity to the pieces,'' Nicoll says. ''I'm not about dressing for sexuality or status, but for personal expression, for self-confidence, not dressing for others.'' T

hat's a whole lot of meaning to stitch into any collection but, Nicoll says, it's possible because design is also a collaboration with his ultimate customer. ''It's why a lot of my pieces are separates, put together on the catwalk as an outfit, but very easy to deconstruct and reassemble into your own wardrobe,'' he says.

''That makes it about interpretation, not me being dictatorial.'' In his own recent collection, his best seller was an oversized silk T-shirt dress, adaptable to most girls and women. ''It's not age-specific or body-type-specific,'' he says. ''But with a sense of freedom, fluidity and modernity.''

Nicoll's own wardrobe - navy blue from collar to shoe soles bar a peppering of white in his shirt checks - is an eloquent clue to his design philosophy: ''I used to fight against the discipline of school uniform,'' he says, ''I'd go op-shopping; clashing patterns and colours, a grungy look. When I was young I was shy, I used clothes as a liberation. Now, I have a self-imposed uniform - I wear entirely navy - and I like that strictness and discipline.''

His penchant for contradiction is also evident in his choice of muses: one, exotic French actress Josephine de la Baume; the other, English artist and shocking feminist rebel in the 1970s, Linder Sterling. ''I am about juxtaposition,'' Nicoll says, quite unnecessarily.