One of the great boom businesses internationally these past few years is the “Pop Up” store, though, like most people, this is a retail phenomena one tends read far more about than actually experience.

For those who have never heard of this marketing marvel, Pop Ups are temporary stores, frequently with time specific merchandise, designed to target fashion forward shoppers, assumed to be obsessed with limited edition of collections.

Though not a new phenomena, it’s used by luxury brands which is relatively recent, and, somewhat ironically, the claim for being the first Pop Up is generally given to mass marketer Target, which opened a temporary 1,500 square-feet store in Rockefeller Center to celebrate Isaac Mizrahi’s affordable women’s line on Sept. 4, 2003. Its life cycle – a mere six weeks, yet Target judged the brief boutiques, a success. One year later it towed a barge-boutique up the Hudson River for the following Christmas season.

This summer, however, Pop Ups popped up in Paris, something of shock in a traditionalist culture like France, with openings by Maria Cornejo and Uniqlo, though the store of the moment was very much Prada’s remarkable “Brief Boutique”.

Inspired by Pont Mirabeau, the store’s huge photo facade features the same charming rusty green arches of the 1893 steel bridge on the Seine. Its entrance door is flanked by a photomontage of two of Mirabeau’s key statues – Le Commerce and Abundance, giant goddesses perched on the prows of trading ships entering Paris, by sculptor Jean-Antonin Injalbert. Even the display cases mimic the Mirabeau’s famed steel shapes, all-the better to display Prada’s latest Death of the Nightclub collection.

The brainchild of architect Roberto Baciocchi, the store will close late December, when Prada’s Left Bank flagship, also by Baciocchi, reopens after renovation.

Not that Prada are new to Pop Ups, they opened a one-week version last year for the duration of Art Basel, the planet’s most important art fair. Prada even created London’s coolest temporary nightclub, The Double Club, a restaurant-bar-dance-floor, created by the Italian label’s special events maestro Jan Kennedy, where 75,000 hipsters came to dine in just six months.

Major league French brands have popped up all over the globe – Louis Vuitton partnered with Comme des Garcons last year, Hermes, opened a temporary Hamptons boutique this summer – but mainly, far away from Paris. Comme des Garçons really started this trend for luxury brands with a guerrilla store in Berlin back in 2004.

Other Pops have tickled our fashion antenna this summer in The City of Light, like Maria Cornejo, who boasts fans as diverse as Tilda Swinton and Michelle Obama, and debuted a 22-day store in the Marais that close July 11. With clothes and accessories strewn across the gallery, the mood reflected the DNA of this eclectic Chilean-born, Italian-influenced and Paris-based designer.

Nearby Japanese pop-luxe casual brand Uniqlo debuted in Paris with an “antenna shop” in the western business district of La Defense, before debuting a tiny retail point, again in the Marais, on July 16, due to end Sept 13.

Unlike the origin of their name, which suggests hot toast that needs to be eaten quickly before going cold, Pop Ups can last anywhere from three-days to one year, at which point they are often termed “guerilla boutiques”. Though, Uniqlo will extend the concept by retailing similar merchandise in Colette, this city’s coolest big boutique that feted the arrival of the Japanese brand on Sept. 1.

Of course, though they certainly generate gazillions of media stories, it’s difficult to know just how much Pop Ups do well for any fashion brand’s business.

In my experience, few things in fashion are less reliable than retailer’s sales claims for designer brands. As my old mentor John Fairchild used to yell at me: “Beware of buyers. They are all liars!” I’ve been to more than one trunk show in my time which attracted less than a dozen clients, and yet the following the day the store manager insisted the event generated 250,000 dollars in sales. As if…

But that was not on mind when I wandered into the poetically romantic Prada Mirabeau, where one feels transported under the arches of the bridge, inspiration of one of the great love poems of the French language, “Pont Mirabeau” by Guillaume Apollinaire.

Pont Mirabeau Sous le pont Mirabeau coule la Seine Et nos amours Faut-il qu’il m’en souvienne La joie venait toujours après la peine

Or in Angle Saxon: Under Mirabeau Bridge the river slips away And lovers Must I be reminded Joy came always after pain

And we thought shopping was painless, maybe not at the cash register.