The Local Government Commission Act of 1946 implemented many of the recommendations of the Select Committee which investigated local government in 1944–45. The Act established a permanent Local Government Commission of four members, two of whom were nominees of local authority associations. The Commission was charged with the continual review of the functions and districts of all types of local authorities. Although not recommended by the Select Committee, schemes for the union, merger, or abolition of local authority districts were made subject to confirmation by a poll of electors. This Commission achieved some minor successes, but its efforts in 1949 to reorganise local government in the Christchurch and Auckland urban areas — the two areas where reorganisation was considered essential by the Select Committee — failed, largely because of political considerations. These two failures seriously affected its status, so much so that in 1951 a Bill was introduced providing that it be abolished and that future reorganisation be conducted voluntarily. The counties and municipalities who, while dissatisfied with the Commission, could not agree on alternative procedures, opposed the Bill, which accordingly was not proceeded with.

In 1953 a new Local Government Commission Act adopted another approach. It reconstituted the Commission as a three-man body with different personnel and curtailed its powers. Rabbit boards had already been removed from the jurisdiction of the previous Commission. The 1953 Act provided similarly in respect of electric power boards also. Hospital boards were removed from the Commission's jurisdiction in 1957. Unlike its predecessor, the second Commission was not empowered to initiate reorganisation schemes of its own accord, while petitions for polls on its schemes could now be made by 5 per cent of the electors instead of 20 per cent as previously required. This latter provision was offset to some extent by the fact that the majority required to upset a decision of the Commission was changed from a bare majority to 60 per cent of the electors who cast valid votes. An appeal authority was constituted to hear appeals against the Commission's decisions. The 1953 Commission, not unnaturally in view of these considerations, achieved very little in the way of consolidation of the local government structure.

Continued dissatisfaction with the cumbersome local government structure and the resulting overlapping and diffusion of responsibilities, both within local government and between local and Central Government, led to a further intensive inquiry by a parliamentary Select Committee in 1960. This Committee firmly recommended that the Local Government Commission be completely reconstituted, that many of the powers possessed by its 1946 counterpart be restored to it, and that it be given additional powers. The Local Government Commission Act of 1961, which came into force on 1 January 1962, gave effect to many of these recommendations. The new Commission has three members, none of whom is nominated by local authority organisations. It may initiate inquiries of its own motion or on request and is authorised to carry out investigations and to report to Government in respect of the establishment of any new form of local government in any area. Its schemes for reorganisation of territorial authorities within the existing structure are still subject to polls of electors, but only in certain cases, and the minimum number of electors who may request a poll in these instances has been increased to 15 per cent. Polls may nullify the Commission's schemes only if, when more than two-thirds of the electors vote, there is a bare majority of valid votes against a proposal and, when two-thirds or fewer vote, there are 60 per cent of the valid votes against it. The new Commission is also empowered to adjudicate where local authorities cannot agree on financial adjustments arising from an adjustment of their boundaries. Provisions for appeal against the Commission's decisions have been retained. The 1962 Act, however, did not implement the 1960 Committee's recommendation that electric power boards, rabbit boards, and hospital boards should be brought within the jurisdiction of the Commission.