This paper analyzes the impact of applying vessel detection technology using satellite images (vessel detection system, VDS) to complement air patrols for fisheries enforcement and control. Due to limited fisheries enforcement budgets there is the need to allocate costs efficiently among competing control tools. This paper focuses on assessing the benefits of using VDS jointly with VMS (vessel monitoring system) and air patrol surveillance to improve effectiveness of controls. A statistical model to estimate the number of inspections was developed and was used with enforcement costs data as reported by a number of EU countries. The result of applying VDS in fisheries enforcement is presented in one of the most demanding fisheries enforcement contexts: the Mediterranean bluefin tuna (BFT) fishery.