National parks represent the largest areas where absolute protection is given and nature is preserved as far as possible. Ten parks totalling 5,019,388 acres have been constituted and are administered under the National Parks Act of 1952. Wilderness areas set apart within national parks have development restricted to foot tracks to ensure the preservation of the natural state. By 1961 five wilderness areas had been set aside in four parks. The National Parks Act also provides for the setting apart of special areas for the preservation of any unique flora or fauna, entry to a special area without a permit being forbidden. One such area has been set apart in Fiordland National Park to protect the only known habitat of the flightless notornis or takahe.

The Reserves and Domains Act of 1953 governs the reservation and administration of public reserves, many of which are set apart for scenic purposes. Positive action to reserve land for scenic purposes was taken with the passing of the Scenery Preservation Act 1903 which set up a Scenery Preservation Commission (later replaced by a board) to report on land worthy of preservation. This responsibility now vests in the Minister of Lands. Nine hundred and fifty-two areas, totalling 683,334 acres, have been set apart as scenic reserves including some reserved primarily for historic reasons. The Minister of Lands is responsible for administration through the Department of Lands and Survey and is assisted in general oversight by the National Parks Authority. Local administration is in the hands of local authorities, scenic boards, or Commissioners of Crown Lands. Public reserves may also be set apart as wilderness areas.