Growing city regions are in between the poles of high land and housing prices and national land-saving targets. The mobiliza-tion of building land to create living space and the reduction of new land take represent a conflict of goals that can only be resolved by taking an integrated look at the instruments for meeting both challenges. In order to address this conflict an-alytically, a regional causal loop diagram is used to map the complex mechanisms of action between housing markets and new land use for housing in core cities and their hinterland and to use it as a theoretical framework. Using a mixed-meth-ods approach, trends in residential development as well as municipal solution strategies in German city regions are inves-tigated. The results show increasing land use efficiency in core cities and the dense hinterland, with simultaneous high, price-induced migration gains in the less dense hinterland, where single-family housing still dominates. It becomes evident that the questions about land saving in the hinterland and housing in core cities have to be considered mutually. The regional land take can only be minimized if affordable and attractive housing is provided in the core cities, especially for families. For this, a more consistent use of existing land policy instruments in combination with a regional commitment to higher densities, especially in the hinterland, is necessary.