The professional life expectancy of a top model was never good. When asked about the prospects of a group of twentysomethings, Cathy Gould, the director of Elite Model Management, once famously said: "They are too old to succeed in a field where much of the talent is recruited out of school."
However, a seismic shift is under way in this most image-obsessed of businesses. While waif-like youngsters were once the order of the day, it is now glamorous women in their forties and fifties who are the new stars of the industry - taking the plum contracts and fronting international campaigns for major fashion houses and cosmetics companies.
And some former models, who were told their time on the catwalk was up two decades ago, are being sought out for a return to the spotlight.
Demand for mature women is such that leading modelling agencies on both sides of the Atlantic revealed to The Independent on Sunday that they are struggling to cope with the number of bookings.
They say that annual growth in the sector has increased by between 30 and 40 per cent over the last three years - and it is continuing to rise. In March, the latest high-profile example of this trend will be unveiled, when Christian Dior introduces Sharon Stone as its new face - just days before her 48th birthday. Last November, Miuccia Prada went even further, signing 52-year-old Kim Basinger to front a campaign for her Miu Miu brand. Versace, too, has been quick to apply the old "age before beauty" adage to advertising, using Madonna, 47, in promotions last year.
It is a trend that has taken many in the modelling industry by surprise. At London-based Models 1, one of Europe's leading agencies, they have begun re-signing older models, who may have left the profession years earlier to have families or pursue alternative careers in the assumption that their modelling days were over.
"In the last couple of years, I've taken models back on to my books who had previously given up at the age of 25 or so," said Elaine Dugas, director of the company's division for older models. "I need these women back now because the demand is there. Fashion for older women has changed completely. It's a huge industry now, and more and more advertisers are realising this.
"The industry has changed completely. Girls' careers used to be short-lived. Certainly by 27 there was no question of them coming back, but a whole new sector is opening up. Visually, people want to see something that is realistic."
Branding experts and marketing managers have seen the effect that resurgent older models such as Twiggy and Marie Helvin - who recently made her professional comeback at the age of 50 - can have on product sales, and are queuing up to replicate it. Last year, Dove soap became one of the first major brands to apply a radical new strategy, using 95-year-old Irene Sinclair as part of its "Campaign for Real Beauty".
The advert asked: "Wrinkled or wonderful?" and was part of a series which also featured 45-year-old Merlin Glozier, alongside the slogan: "Grey or gorgeous?" But that was just the start. Now the entire beauty business is looking to those who were once deemed past it.
One British model given a second lease of life by the phenomenon is Angie Hill, who signed her first, new, major beauty contract - with cosmetics giant Garnier- last year, at the age of 42. "When I was 24 I thought I was too old," said Ms Hill, who appeared on the cover of numerous magazines during the 1980s, including Cosmopolitan, Elle and Marie Claire.
"I had two children and realised I couldn't compete with 16-year-olds, so I quit and started working with my husband in fashion design."
Then last year, Ms Hill - who hails from south London but now lives in Los Angeles - was pushed firmly back into the spotlight by Garnier.
"I'm just shocked and really happy that I can still do it," she said. "I hated looking in magazines and seeing teenagers advertising things that were meant to be for people such as me.
"You can still look good at 40 or 50, so why not show that? Being beautiful isn't just about having tight skin."
Fortunately for models such as Ms Hill, a number of leading companies are beginning to agree. Simon Raggett, a City analyst at Williams de Broe specialising in retail and luxury brands, said it was the spending power of this age group as a whole which was ultimately driving the trend.
"A lot of the spending in this market is by people who are middle aged - particularly in the luxury sector," said Mr Raggett. "People are seeing that their typical customer is not 20 years old, and responding to that in their advertising."
It is a point echoed across the modelling industry: middle-aged women have disposable income like never before, and they are far more likely to part with it if they can relate to the models promoting products to them.
"I guess you could say it's a sign that the fashion industry is growing up a bit, said Jeanna Ridout, director of the women's division at London-based Premier Model Management.
"Advertising agencies and their clients are realising that if they want to sell a product they have to appeal to the buyers - to make them believe in it.
"This is happening so much now that there is a actually a shortage of the right kind of models - there just isn't enough product. High Street stores in particular are having trouble finding them."
For models such as Angie Hill though, there is no trouble at all. In fact, more than 25 years after first entering the profession, she is now enjoying the best period of her working life.
"I am not stopping this time," she said. "As long as people will book me, I will work. I met a woman at a party last week who was 63 and had just done a Dolce and Gabbana campaign. And she looked great."
The Twiggy Effect: Supermodel reborn sparks Marks success
The comeback of Britain's original supermodel last year is behind the revival of one of Britain's most enduring high street retailers. Marks & Spencer's fortune began to improve last October when Twiggy - four decades after her discovery as a 16-year-old in 1966 - was hired for television adverts and billboards promoting the store's new range.
Sales rose 2.9 per cent in the 13 weeks to New Year's Eve, which contributed to a record 20 per cent rise in profits. The share prices rose 50 per cent in the past three months, and the retailer is keen to build on the success by focusing on womenswear.
The chief executive, Stuart Rose, said: "I believe our volume market share has improved and our market share in full price clothing has stabilised for the first time in two years."
Twiggy, 57 this year, is proud of the successful campaign, even though the brand may not be quite as cutting edge as she was once accustomed to. "I defy a single British woman to say she hasn't bought anything from Marks," she said. "They do the best undies anywhere, and I have tried them all over the world."
Twiggy, real name Lesley Hornby, emerged in Sixties London after she was spotted at 15 in a Neasden hairdressing salon. Although she retired at 20, her 21st-century rebirth has also gathered pace on the other side of the Atlantic, where she has become a celebrity after appearing as a judge on the hit reality TV show, America's Next Top Model, hosted by fellow supermodel Tyra Banks.
"The network that screens it was going down before this show; now it is doing brilliantly," Twiggy said. "Children have Top Model parties; if I go into a supermarket in Los Angeles without make-up, feeling very unmodel-like, the shop assistant will say, 'Surely you aren't going to get rid of so and so?'"
Twiggy believes the renaissance of older models will grow. "Baby boomers are getting older, and they have the disposable income," she said. "It's a huge market if you get it right."
Sharon Stone, 47
Christian Dior will unveil Stone as the face of its new Capture skincare line in March, describing her as "a beautiful and desirable woman in her 40s who is clever and independent". A Christian Dior spokesman added: "Sharon says that she feels more beautiful today than at 20 and I was thrilled to hear this. There are so many women in the UK in the 40-plus age group who will identify with her and who are also enjoying the benefits of taking good care of their skin. The mother-of-two, famous for her roles as an actress, recently recovered from a brain haemorrhage and plans to combine modelling with film roles. "I've still got a lot to offer - I'm a really good professional," said the actress.
Angie Hill, 43
Signed her first major beauty contract last year at the age of 42, becoming the international face of Garnier's UltraLift range.
Angie had previously left the profession in her late twenties, after having two children and moving into the world of fashion design working with ex-husband John Richmond.
"People in their 40s and 50s take better care of themselves now, and there are so many products available to help that process.
Previous generations looked tired, but we don't look like mothers any more.
"Every wrinkle tells a story. People can look at these ads and will be able to say, 'even though I'm older, I don't want to succumb to being withered.'"
Marie Helvin, 53
Returned to the scene three years ago at the age of 50. She has worked with top international designers and modelled stockings for Harrods. Her brands are: Dior, Yves Saint Laurent and Oscar de la Renta. The former Vogue cover girl was born in Hawaii but currently lives in Battersea, London. A former wife of photographer David Bailey, she has also recently been a judge on the Living TV's reality show Britain's Next Top Model. "Modelling wasn't me," she said of her first spell on the catwalk. "At the height of my career I felt like a made-up doll." While she endorses the notion of growing old gracefully, Marie is positive about her return to the front line. "I have wrinkles but they're in the right place."Reuse content