New Zealand is responsible for the administration of three South Pacific territories – Niue Island, the Tokelau Islands, and, until 1965, the Cook Islands. The Minister of Island Territories is charged with the administration of the territories through the Resident Commissioners of the Cook Islands (stationed at Rarotonga) and Niue, and the Administrator of the Tokelau Islands (stationed in Apia, Western Samoa). The Department of Island Territories, with offices in Wellington and Auckland, assists in the coordination of the formulation and development of New Zealand's policy in the territories. It also transmits advice and assistance from New Zealand Government Departments to the territorial governments, runs the G.m.v. Moana Roa, and acts as purchasing agent for the territorial governments.

All islanders born in New Zealand territories are British subjects and New Zealand citizens. The total population in the islands is slightly over 25,000, and a further 8,000 Cook, Niue, and Tokelau Islanders are living in New Zealand.