The following study analyses the handling of environmental interests in planning and decision making processes and questions whether and how the significance of environmental interests can be strengthened. Special emphasis is drawn to the currently much discussed approach of strategic environmental assessment (SEA). The study discusses the potential effectiveness of the instrument in the case study of the European Objective 2 Structural Programmes in North Rhine-Westphalia.Results of the case study: Spatial scale has significant influence on the outcomes of the planning and decision making processes. Above all with conflicting interests at the implementation level, ecological interests tend to be left behind in comparison to economic interests. SEA offers a promising approach to environmental governance for strategic planning and decision making processes. Possible constraints and essential requirements for an effective application of SEA are also discussed in the study.