The spectacular and expensive Water Cube and Bird's Nest stadiums were focal points of the Beijing games, but the future of Olympic architecture may well be found in a box.

Australian architect John Barrow, whose firm Populous is working on the London 2012 Olympic Games infrastructure, says a move towards sustainable games architecture could see the introduction of the "stadium in a box".

His idea is to design and construct something affordable, modular, lightweight and flexible, which can be modified and transported from host city to host city.

Mr Barrow said such a concept would mean hosting an Olympic Games could be made more affordable, and cities wouldn't be left with venues they had no use for after the event.

"You won't see the big statements like Beijing, or even Athens, I don't think, because countries just don't have that sort of available funding anymore," Mr Barrow told AAP.

"To put on an Olympics like London, it's £9.23 ($19.89) billion all up, and that's really at the bottom end of the budget. If you're a third world country, you will never have the funds you need to build a full-on, 80,000-seat stadium for an Olympics or a major international event.

"So let's be more modest about the architectural iconography and be more practical about this - it can still be fabulous and beautiful and very dynamic and maybe iconic, but it will be something which is sustainable because it's so much lighter."

Mr Barrow said the term "stadium in a box" was slightly tongue-in-cheek, but the concept he was talking about was already being put into practice.

In the design for the London Olympics, there are four permanent buildings, and the rest of the sites in the surrounding London boroughs will be returned to parkland after the games.

"(This technology) is here now, it's achievable now," Barrow said.

"What we're doing with the London Olympics, the stuff you're not seeing, is the design of the temporary venues, which involves this exact thinking.

"It's quite exciting that when we look at projects now, we'll look at a core facility which is permanent, which houses all the VIPs and all the things you need, but the rest of it, frankly, can be very light touch, very lightweight and it can be brought in when you need it."

Mr Barrow said the move towards sustainable Olympic infrastructure began with the Sydney games in 2000.

"That was the starting point for our company in thinking sustainably, and the first real attempt at a sustainable Olympic stadium," he said.

"It incorporated fabulous features like the rainwater collection (that) had never really been looked at before, the natural convection up through those big towers from the concourses, and the natural lighting through the roofing.

"But more importantly, there was proper consideration of the legacy and what happens afterwards, and that's the real message."