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.

The people from the suburbs are bringing along their suburban values: cleanliness, orderliness, safety - dullness, in other words. As a result, urban areas are being hollowed out. Just look at Times Square in New York. No more sex shops, no drugs, no homeless people. The area is clinically clean and incredibly dull.

Most old cities are now sclerotic machines that dispense known qualities in ever-greater quantities, instead of laboratories of the uncertain. Only the skyscraper offers business the wide-open spaces of a man-made Wild West, a frontier in the sky.

There is no plateau of resting or stabilising. Once you are interested in how things evolve, you have a kind of never-ending perspective, because it means you are interested in articulating the evolution, and therefore the potential change, the potential redefinition.

Let's put it this way: One can be happy or unhappy in a building. But some buildings make us more depressed than others.

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.

Criticism per se does not worry me. I've always solicited it as part of the design process.