This paper investigates how different kinds of knowledge are mobilised in interactions between the stakeholders, scientists and bureaucrats who are involved in EU fisheries management. It reports on an initiative led by the North Sea Regional Advisory Council aimed at making a long-term management plan for Nephrops fisheries in the North Sea. The sharing of knowledge between the actors is explored using insights from organisation management, focusing on the kinds of resources and efforts that are needed at different boundaries to allow knowledge sharing and knowledge production to occur. The findings point to the challenge of reaching a common understanding between actors when both novelty and high stakes are involved. Experiences gained during this pioneering initiative raise questions about how far it is possible to take a ‘bottom up’ collaborative process aimed at developing management instruments within a setting where there are conflicts of interests between the stakeholders involved.