Cross border co-operation is increasingly viewed as an obvious and logical consequence of an integrated perspective on river management. Consequently, we would expect an increase of cross border co-operation and collaboration in EU member states, through joint planning, co-management or co-implementation in flooding policies, water quality management or river rehabilitation. If we take a closer look at regional practices along member states’ borders however, co-operation is often considered as problematic. To explain this discrepancy it is important to look at the conditions of ‘successful’ co-operation in actual cross border initiatives. We provide a framework to analyse regional initiatives, focusing on the extent of co-operation and differences and similarities in policy arrangements. We apply this framework to three cases at the Dutch–German border and conclude that the nature of the problem structure and related interdependencies and ‘urgency’ (still) are important. Moreover, we stress the importance of policy styles and especially the problematic transition from policy formulation to policy implementation in water management.