Collect to invest: Art Nouveau is the ideal look for the new millennium, argues John Windsor

The millennium will have an Art Nouveau look. The year 2000 coincides with the centenary of the Paris Exposition Universelle that established Art Nouveau as a major force in art and design. Already, curators of European museums are vying to display important pieces of Art Nouveau glass, furniture, metalwork and poster art owned by private collectors. In London, the V&A's contribution will be a big exhibition, Decadence and Dreams: Art Nouveau 1890-1914.

Canny investors are already keying in "2000: Art Nouveau" in their electronic pocket diaries and casting around for what to buy.

Glass by Galle, Tiffany, and Daum - fragile, but more portable than furniture - looks a good bet. With its swirling organic decoration it is the quintessence of the Art Nouveau ideal of applied art - literally, applying art to everyday objects, an ideal that the year 2000 will endorse.

After the spectacular crash of Art Nouveau glass in 1991, when the Japanese, having bid stratospheric prices, made a dramatic withdrawal from the market to attend to their own financial crash back home, the names of Tiffany, Galle and Daum have given investors the jitters.

But since then, prices have bottomed out, and new collector-investors - Americans, Greeks, Swiss, French, Italians - have cautiously entered the bidding, pushing prices up to mid-Eighties, pre-crash levels.

The $470,000 (about pounds 287,000), bid at Sotheby's New York last December for an enchanting Galle wisteria table lamp, made in the magic year 1900, is an "immensely gratifying result", according to Philippe Garner of Sotheby's London. It may not be a patch on the crazy world-record for a wisteria lamp - 4,995,000 French francs (about pounds 500,000) - paid for a less exquisite 1900 specimen at Sotheby's Monte Carlo in October 1990, just before the crash. But it shows that collectors are bidding confidently without taking leave of their senses.

Vendors, no longer fearful their Art Nouveau glass will be left on the block, are consigning more of it to auction. At Mr Garner's auction on Friday 20 March there are 41 pieces - mainly vases and table lamps - by the Frenchman Galle, 39 by his one-time co-worker Daum, and five by the American Tiffany. Mr Garner has raised the minimum lot value to an up- market pounds 1,500.

The forthcoming sale includes a 24-inch high Galle wisteria table lamp, more than three inches taller than the one that fetched $470,000 in December. It is estimated at what seems to be a knock-down pounds 35,000-pounds 45,000. But it is not as fine. It is acid-etched but not hand-cut. The finest Galle has several kaleidoscopic, multi-coloured layers of glass, some worked into the surface while still hot and then both etched and hand-carved, using a wheel like a dentists' drill.

The need to appreciate the phenomenal craftsmanship should - in an ideal world - deter crass speculators from bidding blindly for anything by a known Art Nouveau name. The price that will be paid for this month's wisteria lamp will, hopefully, indicate a discriminating market capable of restraint. A silly, high price, would raise fears of another boom-and-bust cycle.

For slimmer wallets, the sale has half a dozen Daum vases estimated in the pounds 2,000-pounds 6,000 range. It is also worth looking at glass designed by lesser names, such as the Austrian Loetz (estimated from pounds 1,200), whose prices are rising on the coat-tails of the better-known Daum and Galle.

Originally a fashionable, avant-garde style, Nouveau Art is still with us after well over a century. Its revival in the Sixties may have faded, but it refuses to go away. Mr Garner says: "It has earned its credentials as a mainstream subject - not in fashion, but not in danger of going out of fashion, either - and I don't see why it shouldn't continue to maintain its position in the long term".

Fun for investors will be to assess just how closely the spirit of Art Nouveau chimes in with the spirit of the millennium. Its strength is that it is not just a style but a movement, with ideals that are cherished today more than ever. It stands for the synthesis of art and craft, for the humanisation of mass-production. And its florid abundance offers a dream of plenty to a population tired of arid minimalism and the dour philosophy of "small is beautiful". A minus point is that its decoration is sometimes "applied" in the worst sense - that is, as an excrescence.

Art Nouveau's runaway lines - the swirling hair of half-clad maidens draped with lilies - make it heady, exotic, mysterious. When all the design history has been chewed over, it is perhaps this quality that gives it its deepest appeal. You might say that Nouveau Art is dead weird. But, these days, aren't we all?

Applied Arts from 1880: Friday, 20 March, (10.30am), Sotheby's, 34-35 New Bond Street, London W1 (0171-293 5000).