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.

In a city like London, the fact that cultures live together and cross-fertilize is a beautiful and natural thing. The many cultures in Amsterdam contribute to the city's high level of craziness - something which every interesting city should offer. But sometimes immigrants can live in parallel worlds which can exclude others and not be very attractive.

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.

I like what Barcelona is doing. This city almost perfectly combines its natural advantages with cultural attractions, IT parks and first-rate educational opportunities. The same applies for Dublin, which manages to achieve a blend of complexity, tolerance and artistry and makes a point of not devoting every part of the city to the tourism industry. Sometimes creativity also means forgoing short-term profits and simply saying no.

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.

All cities have one key resource: the special abilities of the people who live in them. You just have to find out what they are. In the Australian city of Adelaide, for example, which is overshadowed by Sydney and Melbourne, I discovered a number of experts in the penal system. I advised them to work with these special skills.

Hamburg will have a new and important attraction with which it can distinguish itself from other cities. But the important thing is that activities should not just be limited to the building, but that the concert hall should symbolize a general mood of creative rejuvenation.