Port state measures provide a powerful and cost-effective means of combatting IUU fishing. The 2009 FAO Agreement on Port State Measures (PSMA) was the first binding international agreement to specifically target IUU fishing, preventing vessels engaged in IUU fishing from using ports and landing their catches. Its effective implementation will ultimately contribute to the long-term conservation and sustainability of marine resources and ecosystems. 

With the same aim, a 2016 GFCM recommendation lays down a minimum set of standard measures for regional port states to apply when foreign vessels seek entry into or use their ports. Defined inspection and enforcement procedures are followed to verify that such vessels have not engaged in IUU fishing, thus preventing any fish caught illegally from entering into national markets. This reduces the economic incentives for perpetrators to continue to operate. The GFCM has taken a number of actions under the provisions in the recommendation to ensure a robust implementation of port state measures in the Mediterranean and the Black Sea, ranging from the creation of a regional port registry to the setting up of a port state database.