In light of recent drastic changes in national security concerns, new systems are being considered for future military implementation. One of the major systems under consideration by the Advanced Research Projects Agency is the Mobile Offshore Base (MOB). The MOB entails essentially two to six self- propelled, floating platforms that are connected and used for military presence and/or war-fighting purposes. This thesis examines the question of whether the MOB should legally be considered a warship, a merchant vessel, or structure/ installation. This question is Important for the answer implies where on the ocean and under what circumstances the placement of the system complies with international law. After a brief review of the national policy with respect to presence and the problem of reduced access to overseas bases, the thesis examines the legal implications of the MOB. The legal analysis starts with the United Nations Law of the Sea Convention (UNCLOS) that entered into force December 16, 1994. Gaps in UNCLOS definitions and policy are explained by general concepts of international law and, where needed, municipal law. The thesis concludes the MOB should be considered a ship and should be given warship status by the United States Govemment.