This document discusses demographic change and intergenerational solidarity. It notes that demographic change, including population aging and decline, presents challenges for urban management. The document then provides details on the causes and consequences of demographic change in Europe and Germany. This includes longer lifespans, lower birth rates, and out-migration leading to an aging population and shrinking workforce. Consequences discussed include impacts on housing markets, social infrastructure, employment, and economic competitiveness. The document concludes by examining policy responses at national, state, and local levels that aim to foster active aging and sustainable development in the face of demographic change challenges.