The Baltic Sea region, like other economic areas in Europe, is facing significant demographic challenges. There are noticeable differences within the region. While the eastern Baltic Sea countries are experiencing negative net migration, countries in the western part of the Baltic Sea region are attracting immigrants. Developments within countries are also heterogeneous. Economic centers, in particular, often benefit from population inflows. What demographic trends will influence the future development of these countries? And how will Baltic Sea cities be affected by these trends?