The aim of this study is to describe and communicate a proposal for a new tool for assessing ecosystem services in marine spatial planning in the Nordic countries. The tool is based on a stepwise methodology on how to include ecosystem services assessment in maritime spatial planning processes by providing improved knowledge in all sustainability dimensions; ecological, economic and social desirability. This simple and transparent methodology is also intended to be used in the stakeholder participation, to raise awareness, to create understanding and acceptance, and to help reaching an agreement in the case of conflict regarding the use of marine space.