European fisheries activities are subject to a hierarchy of regulatory authorities. This raises questions regarding the implications of strategic interaction between different authority levels concerning the regulation of these activities. We apply a bio-economic objective function where fishers and regulators have environmental, economic and social preferences, and where fishers are subject to the aggregate of the regulations set by the various authorities. We analyse one situation where EU authorities set their regulation first, followed by national authorities’ regulation, and one situation where the two regulators set their regulations simultaneously. Using data from a survey on preferences among fisheries stakeholders combined with data from the UK nephrops fisheries, this study shows that a hierarchy of regulators with similar preferences will yield higher unit regulations, i.e. higher taxes or higher subsidies than a situation with one regulating authority. When regulators have unequal preferences we may get a situation where one regulator induces a tax on effort, whereas the other offers a subsidy. In this situation the aggregate unit regulation becomes uncertain.