LONDON, United Kingdom — It began at Paris Fashion Week two years ago, when Vetements sent its Autumn/Winter 2015 collection down the catwalk, full of its instantly familiar oversized silhouettes: grunge ditzy-print dresses, bulky bikers and bombers, thigh-high leather rodeo boots and those re-worked vintage Levi’s, now the brand’s signature jean.

Net-a-Porter’s global buying director Elizabeth von der Goltz pinpoints that as the moment when denim, which was on the outs for so many years, really became “cool” again. “Demna re-worked vintage rigid Levi’s in an almost couture way — everyone was vying for them,” she says. According to Von der Goltz, the £1,020 ($1,340) jeans “sold out immediately” on the luxury shopping site, and continue to do so season after season.

Certainly, the denim market has been enjoying a long-awaited rebound. Sales in the $13.5 billion US women’s and men’s jeans market grew 4 percent in 2016, according to market research company the NPD Group — the category's best performance in years. Globally, following three years of declines, the jeans market, valued at $92.9 billion, is also expected to grow this year, with men's and women's categories forecast to rise this by 4.2 percent and 3.7 percent respectively, according to Euromonitor.

Folks are choosing not to have six different pairs of Lululemon tights and they’re opting to settle back into their denim.

And as the athleisure trend begins to cool — presenting challenges for gym-to-street brands like Lululemon, Sweaty Betty and others — it would seem denim is clawing sales away from the sportswear category. According to data from retail technology company Edited, the first half of 2017 saw the women’s jeans market grow by 79 percent compared to the first half of 2016. Athleisure leggings, by comparison, grew just 35 percent. “It’s not that athleisure is going away,” says Dio Kurazawa, denim director at WGSN. “It just means that folks are choosing not to have six different pairs of Lululemon tights and they’re opting to settle back into their denim.”

“Millennials are driving the changes,” he notes.

High-fashion brands such as Calvin Klein, Y/Project, Off-White, Balenciaga and, of course, Vetements, have helped along denim’s comeback, says Kurazawa, by catering to Millennial tastes, offering customisation and a move away from the typical five pocket. “These brands really started the denim revolution and a new trend for rigid and vintage denim," Von Der Goltz adds.

Denim stalwart Levi’s is in a prime position to capitalise on consumer demand for vintage styles, given its 164-year heritage, recent collaborations with hot labels including Off-White, Gosha Rubchinskiy and Supreme, and a licensing agreement with luxury label Re/Done, which “up-cycles” vintage Levi’s denim, revamping old designs appeal to a younger generation. “We’re seeing a huge revival in ’90s-style fashion and ‘near-now nostalgia’ sentiment,” confirms Karyn Hillman, chief product officer at Levi’s, who points to the popular high-rise Wedgie model — inspired by the vintage 505, but updated with a little more stretch — as an example. “I think collaborations have really added some sort of equity to the brand,” adds chief marketing officer Jen Sey.

View this post on Instagram Pre-RE/DONE @levis #regram @honestlylauren #shopredone #vintagedenim A post shared by RE/DONE (@shopredone) on Sep 30, 2015 at 1:03pm PDT

In response to the success of re-worked styles, the heritage denim label is ramping up investment in customisation services. This includes expanding in-store “tailor shops,” where shoppers can customise purchases. (Currently, tailor shops are in 100 percent of Levi's UK doors with a heavy presence across Europe; the brand is now looking to recreate this success in the US.) Beyond stores, it has also installed customisation pop-ups at key music festivals, from Glastonbury to Coachella. Sey says the activation “brings value to the consumer,” who, more often than not, is already wearing a pair of Levi’s.

This month, the company launched Levi’s Authorized Vintage, a collection of 50,000 pairs of dead-stock denim it bought back from the secondary market. “Levi’s has had the number one share of the vintage market forever,” Sey says. “We just haven’t actively participated in it [before], so we think it’s high time that we did.”

Other denim brands are also capitalising on the demand for an authentic, vintage-style product. Frame, for example, launched a limited Rigid Re-Release collection that catered to the nostalgia aesthetic in February. While the limited-edition range will not continue into Spring/Summer 2018 due to limited availability, stiff fabrics will still be a key focus for next season’s denim collection.

American brands Lee and Wrangler — both of which come under the umbrella of US apparel company VF Corp. — are also banking on reissues and archive-inspired designs to capture a younger consumer’s attention. “One of the latest capsules that we’ve done with Lee is we’ve gone into the archive to reproduce a retail product from 70, 80 years ago,” explains VF Corp’s jeanswear president Massimo Ferrucci. Wrangler’s Retro Glory collection boasts a similar missive; European stockists of the line include Asos, Urban Outfitters, De Bijenkorf and La Rinascente. “The younger consumer is attracted very much by Americana, by originality and authenticity, by product that comes from the archive.”

But while retro silhouettes and rigid fabrics are on the rise in denim, it would seem that athleisure’s influence has had lasting impacts on the category’s basics, which account for the volume of the market.

When the athleisure craze first blew up, many denim brands responded by investing heavily in stretch denims to try and compete with the fast-growing sector, a focus that continues to pay off. “Stretch is here to stay,” asserts Sey, who notes that Levi’s has actually seen an increase in demand for stretch denim as the fabric has transitioned into men’s lines.

Consumer preferences have changed — comfort has become much more important than in the past.

“Consumer preferences have changed — comfort has become much more important than in the past,” agrees Hillman. “Women generally wear their jeans a little tighter today compared to the past, so we’ve evolved the fits and fabrics to cater to these evolving tastes.” She notes that skinny jeans are still Levi’s best-selling style. “We don’t see that changing anytime soon,” she adds.

Consumer desire for comfort has given birth to the rise of performance denim, another innovation that has become a growth driver for the denim sector. Brands that range from 7 For All Man Kind to Joe’s Jeans are utilising new technologies to enhance existing fabrics and styles.

VF Corp’s Ferrucci says that growth of performance denim at Wrangler — which includes a range of technical fabrics that are water resistant, insulating, cooling, or extremely flexible — has been accelerating fast, “because it’s actually used as a workwear item.” Levi’s too has ramped up investment in similar initiatives, most notably its recent Commuter Trucker jacket, created in partnership with Google. “[It’s] about creating products that meet a consumer need,” says Hillman of the line that was originally created for cyclists in the noughts. “It’s about purposeful design and creative lifestyle solutions to improve people’s lives.”

The casualisation of dress codes — not just in the workplace, but also for smarter occasions (one has four-figure jeans to thank for that) — has given denim a space to become an every-day go-to in a way that athleisure leggings may never be. “She might wear [leggings] to brunch with her friends on a Sunday, but she wasn’t going to wear them out on a date on a Saturday night, and she wasn’t going to wear them to work,” notes Sey. “Denim has a foothold in certain occasions that leggings never will.”

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