The New Zealand Defence Force is the three-branched military of New Zealand. The NZDF is responsible for the protection of the national security of New Zealand and her realm, promoting its interests, safeguarding peace and security, as well as supporting peacekeeping and humanitarian missions. It consists of three services: the Royal New Zealand Navy (RNZN), the New Zealand Army and the Royal New Zealand Air Force (RNZAF), as well as 'tri-service' components. As of June 2023, the NZDF has a strength of 14,996 employees, consisting of 8,669 regular force personnel, 3,260 reserve force personnel and 3,067 civilian members. It is supported by the New Zealand Ministry of Defence (MOD) and is commanded by the Chief of Defence Force (CDF).

The governor-general of New Zealand is the representative of the monarch of New Zealand, currently King Charles III. As the King is concurrently the monarch of 14 other Commonwealth realms and lives in the United Kingdom, he, on the advice of his New Zealand prime minister, appoints a governor-general to carry out his constitutional and ceremonial duties within the Realm of New Zealand.