Since 2002, Germany opts for off-shore wind energy in order to reach the ambitious target of increasing the share of renewable energies. The licensing procedure is regulated by the Offshore Installations Ordinance. The standard investigation concept issued by the Federal Maritime and Hydrographic Agency defines the necessary data collection. In particular, data on the benthic communities, resting migratory birds, fish and marine mammals need to be collected. Until now, the applications for about 100 off-shore wind parks were handed in. The assessment of their cumulative environmental effects, however, is still difficult. As there is hardly any experience in Germany, the environmental assessment can not draw on previous findings. It was only in 2009 that the first off-shore wind park (Alpha Ventus) was implemented. Furthermore, convincing evaluation and forecasting models are still lacking. Until 2017, there will be no compensation of negative environmental effects of off-shore wind power. In order to control the development to a certain degree, in 2009 a spatial plan was prepared for off-shore wind energy in the German exclusive economic zone. This plan has been subjected to an SEA. However, both, the spatial plan and the SEA, have not led to a similar stringent control of wind energy installations as in the German inland. The authors critically consider the substance and the evaluation criteria of the SEA for off-shore wind energy in the German exclusive economic zone.