The principal legislation governing civil aviation in New Zealand consists of the Civil Aviation Act of 1964, the National Airways Act of 1945, the Air Services Licensing Act of 1951, and the International Air Services Licensing Act of 1947, together with amendments to those Acts and a comprehensive body of regulations thereunder.

The Civil Aviation Act of 1964 established a Department of Civil Aviation whose principal functions, inter alia, are to promote and encourage the economic and orderly development of civil aviation, to initiate and carry out surveys into any aspect of civil aviation, to provide for the investigation of aircraft accidents, and to maintain a national meteorological service. The Act enables regulations to be made for regulating civil aviation and for giving effect to the Chicago Convention of 1944 which established the International Civil Aviation Organisation. This lays down technical standards governing the provision of aerodromes, aviation facilities, and many other matters affecting the safety, efficiency, and regularity of air traffic. The Act empowers the Minister of Civil Aviation to establish and operate aerodromes and facilities. Comprehensive regulations under this Act govern the operation of civil aircraft within New Zealand, including Rules of the Air, qualifications of personnel, engineering and maintenance standards, etc. The Civil Aviation (Charges) Regulations prescribe the dues payable by aircraft operators for the use of airports and airways facilities.

The New Zealand National Airways Act of 1945 established the New Zealand National Airways Corporation to provide air services for the transport of passengers and goods within New Zealand and to “satisfy the need for air services within New Zealand”. The Corporation has five directors appointed from time to time by the Governor-General. Provision is made for the Minister of Finance to advance capital to the Corporation. Net profits, after provision for reserves and any accumulated losses, are to be paid into the Public Account. This Act had been modified in important particulars from time to time, and for a period it was clearly intended that the Corporation should have monopoly powers. This is no longer the case, and licences have been granted to private operators, under the Air Services Licensing Act, which impinge upon the Corporation's actual and intended operations, whilst New Zealand National Airways Corporation, like any other operator, must seek licences under that Act.

The Air Services Licensing Act of 1951 set up an independent Air Services Licensing Authority of four persons to hear and decide upon applications from persons wishing to operate air services (air transport or aerial topdressing) for hire or reward within New Zealand. On receiving an application the Authority must advertise it, and any interested party may object, in a public hearing, to the granting of the licence. The authority must take into account any such objections, and must also consider the extent to which the proposed service is necessary or desirable in the public interest, the transport needs of the district proposed to be served, the transport services (air, land, and water) already provided, and other matters. If the Authority decides to grant any licence, it may stipulate conditions. It does, in particular, stipulate that adequate insurance must be taken to cover risks to passengers and others. Licences may be valid for a period up to seven years. Appeals against decisions of the Authority may be made to an Air Services Licensing Appeal Authority.

The International Air Services Licensing Act of 1947 prohibits the operations of international air services except under a licence granted by the Minister in Charge of Civil Aviation. (This Act relates to regular or systematic services; occasional charter flights do not need a licence, but must be separately authorised under the Civil Aviation Act of 1964.) In considering any application for an international air service licence “the Minister shall have regard generally to any international conventions, agreements and arrangements to which the Government of New Zealand is a party”. The Minister may prescribe, inter alia, aircraft types and numbers, frequency of services, and fares.

The general effect of this body of legislation is that any New Zealand operator who wishes to provide domestic commercial services must have his aircraft, aircrew, and maintenance organisation approved by the Department of Civil Aviation, and must thereafter comply with detailed safety regulations administered by the Department. He must also (with some exceptions) obtain a licence from the Air Services Licensing Authority and abide by the Air Services Licensing Authority's economic regulations. International scheduled services require a licence from the Minister under the Air Services Licensing Act and international non-scheduled services need special approval in each case. (A similarly comprehensive system of regulation is enforced by most other countries.)