Some remain great cities, but they shouldn't stand still. They should move in the direction of a knowledge-oriented society. Most cities have to do something to draw attention to themselves and make their particular assets visible on the international radar. I'm not talking about developing countries, but about the United States and Europe.

Another thing I like about German cities - and it's an advantage which they haven't sufficiently exploited yet - is that they are pioneers when it comes to environmental technologies. And green solutions are becoming more and more important.

The Germans are often too bureaucratic, too fixated on rules and not risk-oriented enough. And some of their officials have the feeling that they need to make everything in the cityscape look nice and pretty as quickly as possible. That was particularly apparent in the former East Germany after reunification. Then cities sometimes get a bit too neat and tidy.

Contradictions, most of all, a balance between chaos and order. It needs neighborhoods vibrating with energy just as much as cozy little corners and parks; well-tended, middle-class sections as well as an alternative scene; technology centers for innovative youth and social facilities for older people.

Detroit is an urban hell. But even in this city of the dying auto industry, there is reason to hope, if they manage to combine the creative forces of designers and other intellectual "suppliers" in other ways.

Hamburg is getting a new symbol with its new Elbe Philharmonic concert hall. Such an architecturally impressive building is built somewhere in the world maybe once every five years, if you're lucky.

Creativity cannot be really regulated, but it can be encouraged. The redevelopment or revitalization of a city is an art. It depends on the individual strengths of a place and the will of the leadership to bring about change. The goal is to establish a cultural infrastructure.