Surrounded by water, hundreds of miles from its nearest neighbour, New Zealand is uniquely placed as a maritime nation. Therefore, maritime security is a highly important consideration for New Zealand. Despite this fact, New Zealand's focus on maritime security has not always been strong. This thesis examines New Zealand's involvement in maritime security in the three areas which its security policy focuses on: New Zealand territory, the Pacific, and Southeast Asia. After negotiations for the United Nations Convention on the Law of the Sea (UNCLOS) were successfully completed in 1982, the global maritime situation changed dramatically. Vast areas of oceans which had once been outside any nations' jurisdiction were now the source of territorial disputes. UNCLOS left New Zealand responsible for the fifth largest exclusive economic zone in the world. During the years following World War Two, New Zealand's contribution to Pacific regional maritime security had focused on combating the possible threat from the Soviet Navy. However, following UNCLOS, that focus changed. With its newly acquired fisheries resources, New Zealand began to focus on resource protection through developments such as the establishment of the quota management system and regional cooperation. A shift away from focusing on traditional western alliance obligations was compounded by a falling out with the United States over nuclear ship visits, the signing of the South Pacific Nuclear Free Zone treaty and the bombing of the Rainbow Warrior by the French Secret Service. After the end of the Cold War, New Zealand focused on increasing its defence relations with other nations through a range of activities and organisations including Closer Defence Relations with Australia, the Five Power Defence Arrangements, the Mutual Assistance Programme and the Association of Southeast Asian Nations Regional Forum. New Zealand also carried out a series of defence policy reviews which greatly affected defence policy and force structure, resulting in New Zealand disbanding its Air Combat Force and deciding to reduce the Navy's Combat Force to only two frigates by 2005. During this period, fisheries became a highly significant issue and New Zealand was heavily involved in establishing Pacific fisheries management regimes. Following the terrorist attacks of 11 September 2001, New Zealand's primary focus on security turned to terrorism and other asymmetric threats. Existing regional organisations began to adjust to address asymmetric threats and, in Southeast Asia in particular, maritime security began to feature heavily on the agenda of these organisations. At this time, New Zealand's focus on maritime security was strengthening; this was seen through its purchase of seven new ships for the Navy and its increasing involvement in regional bodies dealing with maritime threats. The future holds a wide range of maritime security challenges for New Zealand. New Zealand must prepare itself for a wide range of unexpected challenges as well as being ready to deal with the threats which have already been identified. New Zealand's current focus on maritime security is strong but it cannot afford to let this slip.