BUILDING OF THE MONTH JIGSAW Bond Street, London W1

By definition, fashion is fast changing. Hard then for architects, who, by inclination and training, tend to design for the long-term future, to come to terms with the fickle world of frocks. If they try to reflect the latest styles in the shops they design, the results are guaranteed to end up the stuff of instant history.

So architects can choose either to swallow their ego and accept the need for one-year-wonder couture design, or else conjure an approach to shop- fitting that serves as a semi-permanent backdrop to in-out, in-out fashion. John Pawson has adopted the former approach for Jigsaw's flagship shop in London's Bond Street. Here is a calmly thought-out and beautifully resolved space that reconciles a desire for lasting and dignified architecture with fast-moving pop clothes.

Pawson's well rehearsed and polished minimalism - a warm, white architectural box, 6m high, 30m deep, with floors of bush-hammered granite, long, langorous stairs, delicate washes of daylight on walls (notably and practically in the changing rooms) - is a perfect foil to Jigsaw's crisp, neat clothes.

Previously the populist chain had paraded a much funkier look for its shops (enjoyably wilful interiors by Branson Coates Architecture). Perhaps, it was Pawson's big, cool store for Calvin Klein that opened on New York's Madison Avenue last year that clinched the deal. Perhaps it was something to do with the spirit of the times, now that more and more people, and particularly women, living in exhausting, miasmic cities, want their homes, their clothes and the places they meet in, from shops to cafes, to be uncluttered, shipshape and modern, yet warm and shot through with colour.

Pawson has been nurturing this theme since taking up architecture in his early thirties some dozen years ago. Clearly his work is now seen as the missing piece in the contemporary urban-design jigsaw. This simple, yet sophisticated Bond Street shop brings high-minded architecture down from Parnassus to the high street, while lifting here-today, gone-tomorrow fashion into the enduring folds of the Mistress Art: a notable, and delightful achievement.