Two of the smartest names in design, Joseph Ettedgui and architect David Chipperfield, have joined forces to create a store just for men.
If there is one quality that distinguishes the diminutive live wire Joseph Ettedgui, it is an unerring sense of timing, so when he says that men need a Joseph shop, he says with conviction: "It's the right time. Absolutely. Now that men buy sportswear, travel, furnish their place, and value style. And not only homosexuals. It is a kind of vanity but it affects all kinds of men, everywhere. Why should they have to shop in a little corner in the store or in the basement? They need to have their own shop."

So today, six days before London Fashion Week when the whole world comes to talent spot in London, the new 600 square-metre Joseph menswear store opens its doors, a block down from Joe's Cafe and the Joseph shop at Brompton Cross, Chelsea.

The new store recognises that many men now have much the same attitude as women to shopping. They recognise - and buy - designer labels, mix them, choose accessories that say something about their personality, and form opinions about their rivals from what they wear. Between browsing and trying things on, modern men aspire to more than an off-the-peg suit and boring shirts and ties. So at Joseph there will be furniture and accessories like Psion wizardry and cameras to buy, watches and sunglasses, digital camcorders and books, and the Milanese luggage called Valtrax which spins around carousels with club-class labels attached.

Among the fashion labels are Gucci, Prada, Helmut Lang, Yohji Yamamoto, Joseph, Jean Colonna, Missoni, Richard James, Ozwald Boateng. "People always love the way English men dress, and Richard James and Ozwald Boateng make that classic style available to everybody, restyling men's clothing and recolouring them," says Joseph, who can't resist throwing in some fashion tips: "This year's pin-stripe suit has a very thin, pale stripe. And two-button jackets are just starting to make a comeback." You've only just thrown one out? Tough.

A familiar sight on the international fashion circuit, Joseph is a kind of Peter Pan at 50ish, with the sort of quizzical, youthful, engaging personality that makes people warm to him. As usual, he has targeted a very wide base of customers for his store, from the account exec in advertising to the City yuppie, the pop star to the footballer. He has worked out what he calls "conceptual living" for them, by which he means "pick an attitude and a lifestyle and go for it". In choosing the merchandise, he describes himself as an "editor, like making a movie in which you need many different things". The shop he likes most is Agnes B, because the spirit of the clothes matches the spirit of the shop: simple, well made, nothing disguised. "A lot of high-street shops have started looking like Armani and it's too much. Just like those noodle places are so right for today, I want shopping to be an amusing, interesting, experience. Accessible. No spin doctors, no PR, no puff."

A concrete Sixties office block about as interesting as an NCP car park has been replaced on site by a coolly monumental glass box - clever this, since it faces sassy Sloane Avenue one way and fogey-ish Walton Street the other. David Chipperfield is the genius behind the architecture, which is evenly punctuated along its concrete party walls by monumental openings to keep the space fluid and dynamic. "Chipperfield's architecture, so tranquil in its appearance, contains in its interior a rich complexity," Alberto Campo Baeza wrote in the foreword to a book on Chipperfield published this year by G Gili, in which he compares "this stupendous British architect to the music of Schoenberg". Certainly, this new store has a certain rhythmic grace in its evenly paced horizontal continuity of the free floor plan. There is skilfully accomplished access between floors with a steel staircase designed like a helix and seemingly fashioned by Twister though it was, in fact, built in shipyards on Tyneside.

So there were pursed lips at Chipperfield's practice when Joseph suddenly called in the interior designer he admires most, another Frenchman, Christian Liagre, and asked him to design the interior with some armoires and chests of drawers in wenge wood, that stolid dark timber that comes with a sustainable rainforest label. Liagre designed the world's chicest small hotel, the Montalembert in Paris, near the Quai d'Orsay, where supermodels and fashion mag editors hang out during couture shows. Nothing too substantial, just that indefinable, gilt-edged, understated luxury which, given that the bedrooms are no bigger than cat boxes, is quite something.

Joseph liked the hotel so much that he commissioned Liagre to design his own house in Chelsea, where he lives with his young and glamorous wife, Issey, and five-year-old daughter, Gigi. Liagre designed it all in monochrome, in shades of ivory and silver, pewter, and moleskin with elegant bits of dark wood furniture. Liagre's own furniture designs have the look of Ruhlman revisited, that French Moderne movement of the Thirties and Forties with poised feet and a slender profile, beautifully crafted in fine woods. "I don't call it interior decoration. I just like to work alongside people with the right feeling for the mood and spirit of the times," Joseph explains.

David Chipperfield replaced Eva Jiricna as Joseph's architect four years ago, about the same time that Joe moved away from Bauhaus steel and chrome classics to embrace French Moderne. He has designed Joseph's New Bond Street shop and the Equipment chain, another Joseph offshoot, as monolithic concrete shells with fine proportions, relatively uncluttered by merchandise which is coolly displayed in little piles upon concrete and glass shelves.

So was this French designer set to ruin his interiors, even though Liagre admires his building? Frank Lloyd Wright first nailed the architect's distaste for furnishings and fittings when he said: "human beings must group, sit or recline, confound them, and they must dine". Shoppers don't need any of that, of course, and, mostly, are kept on their feet, which is why architects like designing stores, but Joseph sees shopping today as a nurturing experience, "like eating, with many different tastes and palates to be catered for". He wants to make shopping a more relaxed and convivial experience. With that quiet resolve for which he is famous in the giddy world of fashion - and tact, too, for he is a kind man who really admires Chipperfield's architecture - he commissioned the wardrobe and shelf units and tables from Liagre. Like Balinese temple doors, a bit Zen, pillar and post architecture in their own right, they sit handsomely alongside the concrete and glass rationalism of the building. These shop fittings move away from the austere Wagamama noodle and hair shirt aesthetic to a more relaxed and well-heeled international status.

The two styles complement each other: "I hope there will come a time when they realise it," says Joe. "The new art is being able to work across many disciplines with different people and to give space a bit of soul." So now we have had soul food, we have soul shopping. But not in a temple to consumerism

Details (clockwise from top left): Joseph cashmere scarf, pounds 95; Jil Sander leather coat, pounds 1,030; Joseph trousers, pounds 125; Jil Sander shirt, pounds 150; Casio G-shock watch, pounds 69.99; Joseph knit, pounds 110