Meet the older ladies of pre-fall. We’ve racked our brains for a more euphemistic name for them, but then we realised that age, and getting older, isn’t something to tiptoe around. The designers they’re working with certainly aren’t doing so.

For their pre-fall imagery, Roland Mouret and Mary-Kate and Ashley Olsen’s label The Row have chosen to feature something different to the standard model, from the usual 17 to 24 bracket. They’ve cast women in their 30s and beyond for these campaigns. And, to quote One Direction, that’s what makes them beautiful.

‘Fashion is difficult when it comes to aging,’ Roland Mouret explains over the phone. ‘There’s nothing wrong with it, and it’s impossible to avoid. I wanted to celebrate the beauty of maturity and the way you can express that.’

His pre-fall campaign features art collector Tiphaine de Lussy, wife of the artist Dinos Chapman and mother of two, who also worked on the range alongside Mouret. Pre-collections – those which fall in between the catwalk seasons of spring and autumn – make up around 70 per cent of Mouret’s sales. So, while he presents two shows in Paris every year stocked with the sort of younger sylphs you might expect, he also ‘collaborates’ with ‘amazing women’ in between.

"Fashion is difficult when it comes to aging... I wanted to celebrate the beauty of maturity" - Roland Mouret

‘It’s a more personal attitude,’ he says, of working with de Lussy. ‘More intimate, more real. Models will wear anything, but here you have a woman telling you what’s relevant. What will go with what and how she will wear it.’

That sort of insider info isn’t to be sniffed at. Designers are waking up to the spending power of the thirty, forty and fifty-something woman, confident in her appearance and expensive with her tastes. She has the template of Kate Moss, 40 earlier this month, to go on, and the likes of Céline’s Phoebe Philo and Stella McCartney to buy from, designers as stylish in their own choices as they are adept at popularising the sort of chic and practical daywear that they themselves want to wear.

Then there are the adverts - Sam Taylor-Wood, 46, for Net-a-Porter; Bridget Hall, 36, for Prabal Gurung; Kristen McMenamy, 47, pretty much everywhere – the increased catwalk presence of the likes of Naomi, Karen Elson and Stella Tennant, and the street style. We have Carine and Anna, of course, but there’s also Elisa Nalin, Natalie Joos and Lee Radziwill, lesser known age ambassadors (remember, we’re not beating around the bush here) who have risen to prominence as the industry has been thrown open to scrutiny by the internet.

The findings seem to be that older women can often look great – and it isn’t the Fifth Avenue facelift brigade we're seeing more of, but the ones who set store by style rather than surgery. Older women haven’t been this prominent in fashion imagery (or consumer culture more broadly) since the Sixties skewed culture and commerce overwhelmingly in favour of the young. Indeed, the fashion industry is far out in front of film for the way in which older women are treated, according to Cate Blanchett.

It’s evident enough in the revitalisation of haute couture in recent seasons – in the doldrums commercially since its decline at the end of the Fifties, the discipline has found an audience in a new generation of discerning women in their prime, rather than princesses and debutantes.

It’s that very crowd that New York label The Row, a sophisticated and minimalist label that deals with fabrics and techniques of the most luxurious order and launched by the Olsens in 2006 with ambitions as high as its prices, has always had at its heart.

‘The majority of our customers are 35 to 60,’ Ashley Olsen told the New York Times in 2009. ‘I wear a lot of the stuff because it’s basic – it’s that ageless design that we try to focus on.’

That’s why it makes sense for the sisters to showcase their pre-collection – the one which accounts for more than two-thirds of sales, remember – on a selection of models whose ages more realistically match those of their customers.  Linda Rodin, Esther de Jong and Ursula Wallis range in age from 40 to 70. They look fantastic, and intriguing. They pique your interest more than a smiling 17-year-old does.

Roland Mouret is only too aware of that. The women he chooses to work with all have one thing in common – they are not celebrities and, as he terms it, 'a part of their life is already done'.

‘What Tiphaine gave, no young model could have given,’ he says. ‘I work with amazing women who have done something with their lives. They’re more puppeteers than puppets.’

‘We’ve all been 21,’ he continues. ‘We’ve all been Cara Delevingne’s age. But we don’t want to go back to that. We’re older than 20 inside. Age is our identity, it’s our soul.’