legitimacy concerns affected parties' perception and support of a policy decision. This certainly depends on whether the process can be judge as fair the level of trust among different parties is safeguarded. while a decision is legitimate if its outcome is considered in accordance with substantial rules about fairness it might also be considered not legitimate if it contradicts with accepted procedural rules of decision-making. Legitimacy refers to the validity of an authority to govern, which may be linked with democratic status or acceptance by stakeholders. This can depend on the power being delegated to the lowest level at which it can be exercised. In general, four forms of legitimacy can be distinguished, i.e. input, output, process and feedback legitimacy, and who actually contribute, what, where and when throughout this process. Eventually, output legitimacy refers to when objective are not achieved, i.e. when effectiveness is low. Legitimacy in EU marine policy is particularly challenging because of the physical distance it has to different governance levels, nations and stakeholders across Europe.