Prior to 1996, the electorate of Marlborough was represented in parliment under the First Past the Post electoral system, where the candidate representing the region, who gained the most votes entered parliment. From 1996 forward the new Mixed Member Proportional (MMP) system was introduced, reducing the number of electorates, but providing for representation based on the percentage party vote. Under this new system, the Marlborough electorate ceased to exist, and a new Kaikoura electorate was created, covering an area from the Marlborough Sounds to North Canterbury.
Traditionally, Marlborough, and subsequently Kaikoura has elected National Party candidates, however since the introduction of MMP, both Labour and Green Party candidates resident in the region have entered parliment as list members. The current MP for the Kaikōura Electorate is Stuart Smith
Marlborough is one of a handful of regions in New Zealand administered by a unitary authority. The Marlborough District Council is responsible for both providing infrastructure and services, and managing natural resources and providing environmental planning.
In most other parts of New Zealand, a district or city council is responsible for providing services, while a regional council is responsible for environmental management and planning. As a result of the combined roles of the Marlborough District Council, and the geography of the region, it has been claimed that the workload of elected councellors is higher than in other parts of the country.
Marlborough was originally part of the Nelson province, however dissatisfaction with distribution of council expenditure on infrastructure resulted in Marlborough separating from Nelson in 1859. As a province, Marlborough struggled financially, and had to rely to a large extent on services from central government. Provinces were abolished in 1876.
Marlborough was divided into initially three, and later four counties, Sounds, Wairau, Kaikōura, and later Awatere. Blenheim and Picton operated as boroughs. Blenheim was the first town in New Zealand where ratepayers directly elected its mayor. The Sounds was in an unusual situation in that it was a county, but had no governing body to levy rates or provide public works. Marlborough County Council was established in 1922, and later absorbed the Sounds and Awatere. Later in 1979, a Marlborough united council was established.
The Local Government Act 1987 abolished the individual councils and established the Nelson-Marlborough Regional Council, Marlborough District Council, and Kaikoura District Council however the arrangement was short lived, and Marlborough became a unitary authority in 1992 while Kaikoura District became part of the Canterbury Regional Council (Ecan).
Marlborough health services are provided by the Nelson Marlborough District Health Board (DHB) based in Nelson. Marlborough elects representatives to the board every three years at the same time as local body elections. Funding is allocated to the board by central government based on population. Due to Marlborough's large itinerant labour force, official population numbers are likely to be considerably lower than the actual population at any time, resulting in funding shortfalls, and problems maintaining services levels. A number of board members are Marlborough based. A major redevelopment of Wairau Hospital with a budget of $45.7 million began in 2008 and was completed in 2010, with most of the old hospital replaced with a completely new single storey steel clad building. The main contractor was Hawkins Construction, with Robinson Construction involved as a significant subcontractor.