On November 25, 2009, during its governing conference in Rome, the Food and Agriculture Organization of the United Nations (FAO) approved a new treaty aimed at closing fishing ports to ships involved in illegal, unreported, and unregulated (IUU) fishing. This article is designed to give an illustration on the development of efforts by the International community as a response to the problems brought by IUU fishing practices. It will start with a description on the background, then on port state control. It will then be followed with an anlysis of the International legal basis for port state jurisdiction. The next part will discuss the case of IUU fishing, and finally on the FAO Model Scheme on Port State Measures to Combat IUU Fishing, and the recent Agreement on Port State Measures.