In the education field, there is not just OCAD: at the University of Toronto, Behnisch & Behnisch and Norman Foster are building science faculties side by side. Foster's, coincidentally, will also be a box on (glazed-in) stilts while part of Gehry's reworking of the art museum will consists of a box perched high - in his case, a direct and acknowledged response to Alsop's nearby OCAD. Diamond's opera house and Libeskind's museum are well under way already, with Gehry's gallery and Kuwabara's film house yet to start.

This is a lot of building to happen in a short time, which means that there is a frantic fund-raising operation under way. Although the state has been dishing out the dollars, the majority of the money has to be raised privately. Fortunately the massive $4.4 billion, 10-year rebuilding of Toronto's Lester B. Pearson International Airport by S.O.M, Adamson and Safdie, which has tied up much of the construction capability of Ontario for some years, has reached a pause point with the opening of the new Terminal One, releasing desperately-needed construction workers back into the city centre.

(Historical note: the airport is named for Lester Bowles Pearson, a former Canadian diplomat, prime minister and Nobel Peace Prize winner who was active in the United Nations and is credited by some for defusing the Suez Crisis of 1956. He also introduced the Canadian flag and the notion of English/French biculturalism.)

Alsop, never one to undersell himself, describes OCAD as his "best building yet". He's probably right in one sense, since this is the purest example I have yet seen of an Alsop diagram built. Usually there are more compromises than this on the long road from concept to reality. In this case - though there were the usual budget-trimmings that mostly affected the finishing materials - the concept remains intact. OCAD had a patch of land alongside its buildings that it had earmarked for the extension. Alsop waved that aside, gave it over to an extension of the public park that lies behind the building, and instead placed his extension way up in the air, hovering above the existing buildings, high enough to allow people in the condominiums opposite to see underneath it. An elevator core gives access: you might assume that the red sloping piece leading into the building's underbelly is an escalator housing, but it turns out to be merely an escape stair.