Regional fisheries management organisations (RFMOs) are the primary mechanism for co-operation between fishing countries and coastal states to ensure sustainable fishing globally. This paper aims to inspire and guide RFMO secretariats and member countries in how to focus their effort and investment to step up the contribution of RFMOs to the fight against illegal, unreported and unregulated (IUU) fishing. It does so by measuring the extent to which RFMOs apply best practices against IUU fishing and pointing to the remaining gaps. Information gathered from RFMOs’ resolutions and recommendations introducing conservation and management measures (CMMs), other publicly available sources and direct communication with RFMOs’ secretariats was analysed and summarised into five indicators reflecting the most important management tools targeting IUU fishing at the disposal of RFMOs. Indicators show overall progress among RFMOs, but discrepancies remain, suggesting scope for improvement by learning from best performers.