This chapter examines why policy-making and the governance of the maritime sector differs between its domestic and international activities and why this needs to be the case. Efficiency, safety, security and the environment co-exist as central themes for governance both domestically and internationally but thereafter things diverge. Reasons why governance at an international level differs from that at a domestic level include: Instruments to accommodate these needs include multinational and bilateral bodies including the UN and WTO, along with industrial self-regulation and the abrogation of sovereignty exercised by, for example, Egypt over the Suez Canal, and a variety of European countries (Netherlands, Germany, Hungary, Romania) over the Rhine/Danube. A major issue that needs addressing if governance is to be effective internationally is that of jurisdiction and the need for policing. This, along with the need for limited points of application (commonly ports), administrative simplicity, a commitment by the industry and some form of pressure to self-enforce, all underlies the success or otherwise of international maritime governance.