Top celebrities are wearing it, high street shops are copying it and now investors are acquiring a taste for vintage fashion. "The market is probably the strongest it's been," says Patricia Frost, Christie's director of fashion. "We used to have just one sale annually; now we have two a year.
"A number of agents buy from our sales for celebrities to wear. That is fuelling the market because every time there's an opening or awards ceremony, there's somebody wearing a vintage dress. People buy it because it means you can follow your own tastes and buy something unique that no one else will have."
The top end of the market is label based - what will be popular and head-turning now is the sort of thing that was cutting edge and iconic first time round. But while there are some classics - such as work from Dior, Chanel or Balenciaga - that hold their prices well, this is also a market that is heavily dependent on the changing whims of fashion.
A few years ago, Christie's was selling lots of the Pierre Cardin white patent boots, which are very Sixties. Now, fashion has moved towards the Seventies and names such as Ossie Clark. "Biba was really hot two years ago," says Frost, "but that's gone slightly off the boil, with prices falling by about 20 to 30 per cent." Biba pieces start at around £150 and cost up to £1,000, but Ossie Clark is hard to find now for under £400 and can sell for £1,500 or even more.
Items from the Eighties, with Vivienne Westwood and Azzedine Alaia two of the big names, also sell well. Christie's even sells dresses and suits from the Nineties but these are very much the top-end Yves Saint Laurent and Chanel outfits. With older pieces, remember that early vintage fashion isn't made for today's woman.
Women wore corsets - which are hard to come by today - and many women were much smaller. Even Seventies dresses weren't designed to allow women to lift their arms above their shoulders.
While there's no doubt you can pick up a great outfit, can you make money on your fashion buy? "People are buying for investment," says Frost, "but they are slightly crazy to buy purely for that reason, because a piece might go out of fashion in five years' time. Frost says this is a market suited to enthusiasts. "The key is to think of any gains as a bonus," she says.
But Frost remains positive. "I think it would be good to invest in some Eighties fashion," she says. "It's not making huge amounts, as people haven't come to terms with shoulder pads yet, but they will."
She has several tips. "I think Alaia is one to buy, and early works of Galliano and Alexander McQueen," she says. "You can still find nice things for £50-60 in charity and second-hand clothes shops."
In general, whatever is most fashionable today is likely to still turn heads in 20 years' time. But apart from the truly iconic, older items might be a safer bet. "The most interesting would be pre-war fashion from the Thirties and Forties, with big names such as Chanel," says Frost.
"A Thirties Chanel piece would be several thousand pounds. Pre-war designers are being bought by museums and collectors, so prices are less volatile. In our September sale, we have a 1949 Dior suit that came from a charity shop, and is expected to raise £2,000 to £4,000, so bargains can still be found."
If you enjoy fashion enough to want to collect, buy the cutting-edge designers of the day, such as Galliano, Westwood, McQueen and Miyake, and don't buy a single outfit: also look for the accessories that would have gone with them, as this can really add value.
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