As more and more architecture is finally unmasked as the mere organization of flow - shopping centers, airports - it is evident that circulation is what makes or breaks public architecture.

As more and more architecture is finally unmasked as the mere organization of flow - shopping centers, airports - it is evident that circulation is what makes or breaks public architecture.

But now sustainability is such a political category that it's getting more and more difficult to think about it in a serious way. Sustainability has become an ornament.

I studied in London in 1968. Our school had a separate department of tropical architecture. Of course it was totally unfashionable, partly because nobody wanted to think about colonialism, but basically what you learned there was that, OK, the sun is here, so you should create natural ventilation here - an unbelievable amount of really sound principles that have been completely abandoned, so now everything is air conditioned with big machines.

There are essentially two possibilities. One is to be, shall we say, an average architect and do the same thing everywhere. The other is to let yourself be inspired and even changed by the unique qualities of the place where you're building. We always try to take the second approach.

Prada is extremely directed in terms of communicating what they like and what they don't like. That is actually extremely pleasant because it clarifies very easily what you can do and what you need to do.

Lagos has also had a particular effect on my career. I was there early, and although it was a courageous step to go there and invest on this scale - I went there maybe 20 times - it's also been also super-controversial. There's an old school of thought that somebody like me has no place to go there.Because of colonialism and so on.