The book, based upon extensive research and 480 interviews, argues that european upper middle class are not becoming nomads travelling the world without connections nor barbarians seceding from cities. We develop the hypothesis of the "partial exit" to suggest that many middle class european are happy to be transnationally mobile in order to gain resources and then to come back and to improve their situation in terms of income or prestige. They use changing scales of economic and social organisations (Europe, globalization) in order to promote their interest. In urban terms, by contrast to most of the literature, the books shows that upper middle classes are deeply rooted in cities, keep close networks with friends and families, and play sophisticated games of distance and proximity. In other words they become transnationally mobile to a limited extent, under shelter and they often come back where they were before. Finally, they see themselves as the modernist avant garde of societies.