It is certainly a shop window for art. Given Cincinnati's urban edginess - there was a full-blown three-day race riot here last year, and the underclass is much in evidence - the CAC would have been forgiven for adopting a bunker mentality. Not a bit of it. Hadid has opened it right up with a wrap-round glazed street frontage, with Desmarais' blessing. The message is non-elitist. Not that the CAC members who flocked in their thousands to the opening night looked much like the street bums kept back behind the cordons, but you've got to start somewhere. As for the interiors, says Desmarais, Hadid led the thinking. "At first, we said we wanted all big open spaces that we could break up into smaller spaces, so getting flexibility. But very early on, she said she had this other proposal - she said, I'll give you this set of different-sized galleries, all different heights and shapes and such - and we accepted that as a great plan immediately. Given that we're on a very tight urban corner, I'm thrilled at the array of spaces that we've got."

Hadid managed this in two ways. First by stacking the gallery up high, on four floors plus basement, with daylight coming in from a tall atrium criss-crossed with very long stair-ramps (made by a roller-coaster manufacturer). And secondly, by breaking up the rectangular, shoebox-shaped site with a radiating series of divisions drawn from a geometric starting point some distance away. This is what generated the variety of spaces, while Desmarais' desire to engage with the community generated the foyer spaces. "I wanted to bring the outside in, with the idea of an urban carpet," says Hadid. "In the galleries, we didn't know what they would have there. So the idea was to make as many different 'found spaces' as possible. We designed a kit, from a desk to a wall to a gallery, that would fit together in lots of ways. And for the geometry, we looked outside our boundaries."