Abstract
Research summarized here indicates that, despite a certain degree of success, particularly in the area of environmental protection, German—Polish transboundary planning cooperation is being hampered by considerable lags between political agenda-setting, European Union structural programming, and postsocialist institutional transformation. Furthermore, though German—Polish cooperation institutions have been created largely from the ‘top down’, research indicates that transboundary regionalism must also develop local roots through a slow and gradual process of routinized interaction. The real test of German—Polish regionalism will thus be the development of new networks between public and private actors stabilizing the institutions now in place, but there nonetheless remain questions as to the intrinsic economic development potentials of transboundary cooperation within a context of European integration and expansion.