The athleisure trend, long popular in the U.S., is finally catching on across Europe. As more European shoppers adopt casual style, brands catering to the look — both abroad and in the U.S. — have a major opportunity to win over those customers. And they’re eager to do so.

This week, French fashion brand Sézane launched its first athleisure line. The 23-piece leisure capsule collection includes T-shirts, sweatshirts and leggings made from 100% recycled and eco-friendly materials. The company, which expanded into the U.S. in 2018 with a physical location in New York (adding to its London and Paris stores), is known for its Parisian-inspired pieces, from jumpers to blazers. Founder Morgane Sézalory said the collection is not in direct to response to a shift in the way people are dressing.

“I was looking for sports clothes that were comfortable and that you could really live in, but also good for the environment with recycled materials and also feminine at the same time. I couldn’t find anything in the market that encompassed all three points. I wanted the line to be like the Sézane clothing collection: good basics, with the little details and feminine touch,” said Sézalory.

“It was more about the idea of having pieces you can wear for different occasions, for a yoga class, coffee with a friend or a walk on Sunday,” she said.

Regardless of Sézalory’s inspiration, Sézane’s foray into leisure comes at an interesting time.

In the U.K., 54% more athleisure styles were on the market in 2018, versus 2017. In Western Europe, the sportswear market was valued around $63 billion in 2018, billed at the world’s third-largest market just behind Asia Pacific ($83 billion) and North American ($123 billion), per Euromonitor International. By 2023, Euromonitor International predicted sportswear sales in Western Europe will hit $74 billion.

The opportunity here isn’t just for Europe-based brands, but for U.S. brands that have already perfected athleisure and casual trends. In the U.S., casual-wear sales reached $103 billion for the 12 months ending June 2019, more than half of the apparel industry’s annual sales, per The NPD Group.

“With the emerging trend of European shoppers beginning to dress more casually, U.S. activewear brands have never been in a better position to capitalize on this. Shoppers are less tied to brand names. Advanced infrastructure now makes [international] returns and logistics a breeze. U.S. brands can easily expand into European and U.K. markets,” said Greg Gillman, chief revenue officer at digital marketing agency MuteSix.

The shift is already taking place. At the end of October, men’s casual apparel company Untuckit announced its shift into the U.K., opening two new stores this week, on top of the company’s 80 existing stores in North America. Untuckit said it plans to open more locations across Europe in the coming years. The company reportedly does $100 million in annual revenue.

TechStyle Fashion Group — the company behind Fabletics, Just Fab and Savage X Fenty — is another company already tuned in to the European market. The company has seen success with its Fabletics brand in Europe in the last two years, as a result of consumers adopting more casual wardrobes, particularly in the U.K. and France, a spokesperson for the company said.

Fabletics has brought in over $400 million in annual sales this year, with 85% of sales coming from the U.S. The remaining 15% came from Western Europe, with France representing the fastest-growing market for the company.

While getting set up in global markets may be easy, competition is now at all time high,said Jordan Bishop, partner at creative management platform Storied. Competition for U.S. brands, specifically, will be high as native U.K. brands build up their casual lines. Asos, for example, launched its private-label activewear line 4505 in 2018, while other companies like Gymshark are driving $128 million in annual sales.

“The competitive landscape is different in Europe, so any American brand looking to thrive there needs to tweak its penetration and growth strategies to adapt to that landscape,” Bishop said.

For example, Italian men’s apparel brand Stone Island is way ahead of the competition in terms of tech-wear and innovating new fabric blends, while Puma has a loyal customer base in Europe that’s never really been matched in the U.S., Bishop said.

One thing U.S. brands need to keep in mind when moving into the European market is that a one-size-fits-all approach won’t cut it.

“These trends aren’t consistent across all of Europe, and lumping the entire continent into a single bucket is a definite fashion faux pas. American brands should always look at European markets on the country level, not on the regional level, when making decisions, since the consumer profile differs wildly across national lines,” said Bishop.