Indeed, the purpose of the runway show is to preview collections for buyers and test demand, and not all of what is shown gets made. That is an important distinction from the fast fashion model — which tests styles by producing them, and rapidly moving on to the next — but it still relies on a substantial amount of guesswork. Forecasting is an imperfect science and virtually all brands and retailers have some quantity of unsold goods on their hands at the end of each season. More to the point, using the fashion show to release new styles as frequently as brands do is meant to encourage consumers to buy those new styles, which means they’re adding items to their wardrobes that they don’t need or replacing old ones that are still functional but — specifically because of the new release — simply less on-trend.

Advocates say fashion needs to go further to change the existing system. All the major fashion weeks have put sustainability on the agenda in some capacity, but away from the runways. In London, the British Fashion Council’s Institute of Positive Fashion is meant to position the UK as a pioneer for a circular fashion economy. And in New York, the Council of Fashion Designers of America has organised events focused on sustainability between fashion shows.

There’s no blueprint for what it could or should look like for a fashion show to integrate or define sustainability more clearly, which is not a coincidence; fashion brands have built their business models on selling new goods all the time, and fashion shows are a key way that companies keep that machine running. But that’s where critics see room for fashion to put its greatest asset, creativity, to use — and only by experimenting with new ideas and approaches will it find ones that can work. One way could be for brands to detail the sustainability credentials of a new material in the show notes, or to find a way to integrate messaging about fashion’s impact on the planet or what they’re doing to mitigate it — without greenwashing — into the set itself.

New business models that reduce production and consumption should also have a bigger role during fashion month, McDowell suggests. A few styles in a collection could be only available made-to-order, or some made available with a rental service. The potential scenarios to explore are virtually limitless; the point is to get started, he says. “I think we have to, very quickly, get to changing the systems, and using fashion week as the means.”

The dissonance is, increasingly, weighing on other designers’ minds, too. “We all are going through climate change, we all saw the fires around the world. And coming back with a fashion show in September and just thinking, ‘Are our pants going to be high waisted or low waisted?’ To me, there’s a bit of frivolity,” Balmain creative director Olivier Rousteing said following the brand’s Wednesday night show in Paris. He says fashion brands should be working with their suppliers to change the landscape. “I don’t want to fire a supply chain that doesn’t know sustainability — I want to teach them. I’m not telling you my collection is 100 per cent sustainable. It’s not,” he said. “But you need to start from somewhere.”

Luke Leitch contributed reporting.

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