Besides recovering history and repairing destroyed structures, the continued construction and the new interpretation of existing cities are the most important challenges in contemporary architecture. With their powerful free-standing composition for the GSW Headquarters in Berlin, Sauerbruch Hutton came onto the scene right at the beginning of Berlin’s second period of economic renewal, during which the reconstruction of the urban fabric was being discussed. They had to wait almost five years until the time for their vertical reinterpretation of that segment of the Kochstrasse was ripe that until then was to have represented a complete break with the pre-war Berlin. Their design not only accepts the urban fabric but also the collage character of the new context, one that is to be filled with new density and which creates a flexing sculptural-architectural silhouette in the vertical dimension. In doing so, energy saving technology is used. Thus, their design attains an exemplary status of an ecological architecture which does not dissolve the city but aims to strengthen and modernize it.