Have we reached peak fashion collaboration?

When I went to New York for the unveiling of a high-profile fashion collaboration recently, colleagues and friends asked which two brands had teamed up. Without fail, the answer surprised them — Lululemon and Ganni.

Were the patron saint of leggings and the doyenne of Copenhagen cool really jumping into bed together? Each may be a master of their own game, but what could they achieve by joining forces, other than a nice marketing moment?

Rather a lot, as it turns out. When we descended into the Williamsburg basement Lululemon and Ganni had decked out in leopard print for the glitzy launch event, the collection that awaited us achieved something all too rare in the saturated world of fashion collaborations.

The pieces were at once familiar and fresh, creating something greater than the sum of their parts. There were riotously loud leopard-print leggings, slouchy track jackets with little feminine frills and super-soft, sweat-wicking 1980s-inspired sweatshirts that hung off one shoulder Flashdance-style.

Alexa Chung’s Reformation collection feels so right, it’s hard to believe this is the first time it’s happened

As Ganni founder Ditte Reffstrup succinctly put it: “When a collaboration is good it puts a smile on your face because you can see both brands.” Lululemon’s creative director Jonathan Cheung, meanwhile, called it “a surprise collaboration but not a surprise”.

Together, they seem to have got to the core of what makes a successful collaboration: something bold yet intentional, with pieces that feel all the more covetable because they “shouldn’t work” but do. Little wonder much of Lululemon x Ganni is now sold out — the most surefire marker of commercial success.

It was a similar story for another of the year’s biggest and most unexpected collaborations: between Marks & Spencer’s St Michael label and streetwear brand Aries. Here was a beloved, nostalgic piece of M&S history being resurrected to unite with a cult label known for gender-neutral silhouettes and graphic designs. But anyone who wasted time being confused by the partnership on launch day will have missed the now sold-out pieces, including a leather iteration of an M&S lime green carrier bag that was gone in moments.

Reformation x Alexa Chung

M&S is on something of a collaborative roll this year, no doubt emboldened by the success of repeated collections with designer Bella Freud, who brought her signature irreverent knits to the fashion halls of the high street giant. The Aries moment was followed by an underwear collaboration with Coco de Mer. Suffice to say this London-based brand deals in lingerie that’s a little more risqué than your average pair of M&S pants. And yet, it works, partly because it gives consumers a premium product at a far more accessible price point. It will be interesting to see what M&S does next and whether it can retain the all-important element of surprise and avoid diluting its core product line.

With an experimental mood taking hold, some trusty established partnerships have come and gone without much fanfare. Victoria Beckham’s latest for Gap, for one, gave the sense that this particular partnership may have run its course. It feels like there’s always a Hunter or Barbour collab going on, but the frequency means some really great ones, such as Paul Smith Loves Barbour, don’t get the attention they deserve.

Uniqlo x JW Anderson

JW Anderson for Uniqlo, in contrast, now feels like part of the furniture but no less great for its familiarity. Perhaps it needs to play it safe to allow Anderson to work on everything else he has going on, including Dior, his own eponymous brand and a recent collaboration with Ugg. The latter gave us bizarre-looking “loafer boots” as well as a penny loafer-inspired take on Ugg’s slip-on Tasman style that has sadly sold out.

Another genre of collaboration is the celebrity partnership. Sometimes, this is merely a big name fronting a campaign, but a special few exceptions come from the Kate Moss for Topshop school of collabs. This year’s big hitter is Alexa Chung for Reformation, a collection that feels so right, it’s hard to believe that this is the first time it’s happened.

The 30-piece edit looks how you might imagine a savvy wardrobe department would dress Chung in the film of her life; there are lace-trimmed Prada-esque co-ords, insouciant slips and rich velvet separates, but also logo tees and straight-leg jeans. It works because Chung has a singular sartorial aesthetic and it fits perfectly with Reformation’s.

She says she also called on a few external reference points. “I was reminded of Kirsten Dunst in the 2000s, and the purple strapless dress [from the collection] really feels like a nod to that era,” she says. “I would be lying if I didn’t say I also looked at a lot of images from Sex and the City. It’s elegant, relaxed and effortless, but I think in winter we need that pop of colour to keep things from looking too drab.”

That’s another crucial ingredient in a great collaboration: thoughtful, timely design. Without that, any partnership is doomed to insignificance.