Koolhaas - aged 55, tall, thin, balding, stooped, with an anxious mien and with a style of public speaking that is not so much monotonous as catatonic - is treated as a rock star by successive generations of wannabe architects. He is the David Bowie of the built environment in everything except personal charisma, and the absence of that, strangely, seems not to matter. Why are you famous, I ask him? Why do you have such a following? Koolhaas does not answer the question directly (he almost never does) but nonetheless has a blindingly good response. "I'm still able to disappoint expectations," he replies with a rare smile. "That's an important freedom."

Expectations. He is all about those. Even his name is perfect for the English-speaking art world, an assonance for "Cool House", so it is a bit of a come-down to learn that in Dutch it means "Cabbage Hare", while his first name, Rem, surreally means "brake". Despite his long-term residency in London (weekends here, work in his office in Rotterdam) he has yet to get off the mark with a building in the UK. This is despite the fact that he is regularly shortlisted for our important international architecture competitions - Cardiff opera house, Tate Gallery of Modern Art, the South Bank centre revamp among them - and despite having been schooled in the radical hothouse of London's Architectural Association. But London is for him an escape from work. He loves the city, and expresses that love in Koolhaas-speak. "It has a multi-focal quality," he says. "London does not have an overwhelming identity, rather an accumulation of different identities".