Most of us equate architecture with the idea of permanence; after all, it’s one of the three precepts espoused by the ancient Roman architect Vitruvius – durability, utility, and beauty – that have propelled builders since antiquity. But a new phenomenon, “pop-up” architecture (also known as “temporary” architecture, or even “urban interventions”), has shaken that idea to its very — excuse the pun — foundations.

The scale of the concept ranges from huge to small, from boutiques and grocery stores to entire neighborhoods. The current London Olympics fall full-force in the supersized category, where the imposingly impermanent includes the Basketball Arena (detail shown above), which was intended as a temporary site since inception, with almost two-thirds of its building materials destined for reuse or recycling. The facility’s textured shell and portal frame will eventually travel to Brazil for the 2016 Games.

The realities of difficult economic times have played a large role in the growth of these transformable venues, many of which are easily disassembled or refashioned for longer-term needs, and which come in all shapes and sizes, encompassing all levels of imagination. In Winnipeg, Canada, the pop-up huts (above), designed for those braving the cold as they skated along a frozen river trail, were winners in the temporary-architecture category at this year’s Azure Awards. In New York City, the LOT-EK design firm transformed shipping containers into walk-in “stores,” below, complete with shelf space, cash registers, and fitting rooms. (More amazing examples are featured in the book, Temporary Architecture Now!, by Philip Jodidio.)

An idea that’s “so retro it’s become radical,” according to New York Times writer Allison Arieff (citing, as one past example, the temporary bookshops that have sprouted up along the Seine River in Paris for centuries), Arieff also points to the flexibility inherent in impermanence as an incentive for designers and planners to experiment with new structures and services without the time-consuming bureaucratic burdens necessary for the creation of brick-and-mortar buildings.

As for this year’s Olympics, it looks like London will have served as a testing lab for what is already becoming one of the defining architectural trends of the decade. In addition to the Basketball Arena, both the Aquatic Center and the Olympic Shooting Gallery are scheduled for disassembly and recycling, and the Olympic Stadium itself will be shrunk down to a smaller community venue.

In a twist on the old saying: Now you see ‘em … and now you may see ‘em again.

(Photo/top: Bryn Lennon / Getty Images)