This research project shall develop a scientific basis for the integation of nature conservation issues in Maritime Spatial Planning (MSP). Due to the requirements of the EU MSP Directive and in the light of existing commitments under OSPAR and HELCOM as well as in the implementation of the Marine Strategy Framework Directive the implementation of an ecosystem approach is an essential innovation in national policies. So far, the scientific basis for the practical implementation of the ecosystem approach in MSP is weak. The project is intended to fill existing gaps. Especially within HELCOM (in cooperation with VASAB), but also in other international fora, working groups have been installed in which the compatibility of maritime activities with the spatial dimension of marine nature conservation objectives has to negotiated. This R & D project shall review and revise scientific methods for the implementation of the ecosystem approach and investigate which ecosystem processes and functions are essential for the implementation of the ecosystem approach.