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.

The thing is that I have a really intense, almost compulsive need to record. But it doesn't end there, because what I record is somehow transformed into a creative thing. There is a continuity. Recording is the beginning of a conceptual production. I am somehow collapsing the two - recording and producing - into a single event.

In Lagos there's a really strong case to resurrect strong parts. Embedded in all of it are some amazing pieces of planning, amazing pieces of engineering and interaction. For instance, the campus of Lagos University is stunningly beautiful, efficient and generous, and that needs to be recognised and preserved.

At that time [90th in Lagos], if you drove through the city, you drove through a foreground that always seemed to be incredibly dramatic and incredibly agonised - smoking, burning, incredible compression. In the first year we stayed on the ground and went everywhere. But then in order to discover whether this was the whole story, we rented a helicopter. And we began to understand that this is not chaos but a highly modern system that had been abandoned, then at some point went into reversal, then slowly came out of it.

Manhattan has generated a shameless architecture that has been loved in direct proportion to its defiant lack of self-hatred, has been respected exactly to the degree that it went too far.

Nigeria [in 1990] was all rumour, an unbelievable amount of rumour - largely about crime and almost mythical manifestations of evil.

It was a book [George Packer written on our presence in Nigeria] that was killed by the response of other people. Which sounds quite cowardly, perhaps, but it was the first manifestation of what is currently a really big issue: how political correctness defines the limits of what you can do. In that sense, it was super-exciting and maybe the most magical project we did, but at the same time fraught with mixed feelings.