Over the past 40 years many fish populations in Indonesian waters have been severely depleted. The paper argues that any explanation of these depletions must take account of the nature of the Indonesian state. The Indonesian state is a highly fragmented structure made up of competing components that in many cases have to raise their own revenue in order to function. The nature of the Indonesian state creates the conditions in which fisheries depletions are likely to occur. The paper develops this argument by focusing on the various ways in which Thai trawlers have operated in Indonesian waters and examining how the Indonesian navy's responsibility for enforcing fishery regulations has often clashed with its own interests in fisheries. The paper argues that one way to overcome the limited ability of the Indonesian government to enforce fisheries regulations and to control the movement of fishing vessels into the waters of other countries is to establish a regional regulatory regime that builds on and expands the Southeast Asia Fisheries Development Center (SEAFDEC) advisory body. The paper concludes by examining some of the obstacles that might get in the way of the success of such a regime and proposing ways in which these obstacles can be overcome.