I'd say that my profession ends where architectural thinking ends - architectural thinking in terms of thinking about programs and organizational structure. These abstractions play a role in many other disciplines, and those disciplines are now defining their 'architectures' as well.

There's something really interesting about current urbanism: the only model is the universal model, and there is increasingly incapacity to consider the virtues and the qualities that are there, and then to build on them. The only thing is complete transformation.

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.

The Grid makes the history of architecture and all previous lessons of urbanism irrelevant. It forces Manhattan's builders to develop a new system of formal values, to invent strategies for the distinction of one block from another. The Grid's two-dimensional discipline also creates undreamt-of freedom for three-dimensional anarchy. The Grid defines a new balance between control and de-control in which the city can be at the same time ordered and fluid, a metropolis of rigid chaos.

When we went in the late 1990s, Nigeria was still in a dictatorship. So we didn't go with a mission. It started really with a sort of blankness and open-endedness.

Any architectural project we do takes at least four or five years, so increasingly there is a discrepancy between the acceleration of culture and the continuing slowness of architecture.

The luxury of our position now is that we can almost assemble any team to address any issue.