The role of the Prime Minister is not formally defined, being based on constitutional convention rather than specific legislation. According to these conventions, the Prime Minister is leader of Cabinet (itself a body existing by convention), and takes a coordinating role.
The Prime Minister is regarded by convention as "first among equals" - he or she does indeed hold the most senior post in the administration, but is also required to adhere to any decisions taken by Cabinet. The actual ability of a Prime Minister to give direct orders is surprisingly limited - most of the position's power comes about through other means, such as:
By convention, the Prime Minister is the leader of the party or coalition of parties which has the most seats in the houses of the Parliament. There is also a Deputy Prime Minister, who may or may not be from the same party.
Prime Minister became the official term for the leader of the New Zealand Government in 1893. Before 1893 leaders were called Premier of New Zealand.
Thirty-seven people have held the office since it was established. Some of these people have held it on several different occasions, with the record for maximum number of times being shared between William Fox and Harry Atkinson (both of whom served four times). The longest that anyone has served in the office is thirteen years, a record set by Richard Seddon. The first holder of the office, Henry Sewell, led the country for the shortest total time; his only term lasted only thirteen days (the shortest term actually belonged to Harry Atkinson, whose third term lasted only seven days, but Atkinson served longer than Sewell in total).
| Name | Took Office | Left Office | Party
|
|---|---|---|---|
| Henry Sewell | 7 May 1856 | 20 May 1856 | None
|
| William Fox | 20 May 1856 | 2 June 1856 | None
|
| Edward Stafford | 2 June 1856 | 12 July 1861 | None
|
| William Fox, 2nd time | 12 July 1861 | 6 August 1862 | None
|
| Alfred Domett | 6 August 1862 | 30 October 1863 | None
|
| Frederick Whitaker | 30 October 1863 | 24 November 1864 | None
|
| Frederick Weld | 24 November 1864 | 16 October 1865 | None
|
| Edward Stafford, 2nd time | 16 October 1865 | 28 June 1869 | None
|
| William Fox, 3rd time | 28 June 1869 | 10 September 1872 | None
|
| Edward Stafford, 3rd time | 10 September 1872 | 11 October 1872 | None
|
| George Waterhouse | 11 October 1872 | 3 March 1873 | None
|
| William Fox, 4th time | 3 March 1873 | 8 April 1873 | None
|
| Julius Vogel | 8 April 1873 | 6 July 1875 | None
|
| Daniel Pollen | 6 July 1875 | 15 February 1876 | None
|
| Julius Vogel, 2nd time | 15 February 1876 | 1 September 1876 | None
|
| Harry Atkinson | 1 September 1876 | 13 October 1877 | None
|
| George Grey | 13 October 1877 | 8 October 1879 | None
|
| John Hall | 8 October 1879 | 21 April 1882 | None
|
| Frederick Whitaker, 2nd time | 21 April 1882 | 25 September 1883 | None
|
| Harry Atkinson, 2nd time | 25 September 1883 | 16 August 1884 | None
|
| Robert Stout | 16 August 1884 | 28 August 1884 | None
|
| Harry Atkinson, 3rd time | 28 August 1884 | 3 September 1884 | None
|
| Robert Stout, 2nd time | 3 September 1884 | 8 October 1887 | None
|
| Harry Atkinson, 4th time | 8 October 1887 | 24 January 1891 | None
|
| John Ballance | 24 January 1891 | 27 April 1893 | Liberal
|
| Richard Seddon | 27 April 1893 | 10 June 1906 | Liberal
|
| William Hall-Jones | 10 June 1906 | 6 August 1906 | Liberal
|
| Joseph Ward | 6 August 1906 | 28 March 1912 | Liberal
|
| Thomas MacKenzie | 28 March 1912 | 10 July 1912 | Liberal
|
| William Massey | 10 July 1912 | 10 May 1925 | Reform
|
| Francis Bell | 10 May 1925 | 30 May 1925 | Reform
|
| Gordon Coates | 30 May 1925 | 10 December 1928 | Reform
|
| Joseph Ward, 2nd time | 10 December 1928 | 28 May 1930 | United (Liberal)
|
| George William Forbes | 28 May 1930 | 6 December 1935 | United (Liberal)
|
| Michael Joseph Savage | 6 December 1935 | 27 March 1940 | Labour
|
| Peter Fraser | 27 March 1940 | 13 December 1949 | Labour
|
| Sidney Holland | 13 December 1949 | 20 September 1957 | National
|
| Keith Holyoake | 20 September 1957 | 12 December 1957 | National
|
| Walter Nash | 12 December 1957 | 12 December 1960 | Labour
|
| Keith Holyoake, 2nd time | 12 December 1960 | 7 February 1972 | National
|
| Jack Marshall | 7 February 1972 | 8 December 1972 | National
|
| Norman Kirk | 8 December 1972 | 31 August 1974 | Labour
|
| Bill Rowling | 31 August 1974 | 12 December 1975 | Labour
|
| Robert Muldoon | 12 December 1975 | 26 July 1984 | National
|
| David Lange | 26 July 1984 | 8 August 1989 | Labour
|
| Geoffrey Palmer | 8 August 1989 | 4 September 1990 | Labour
|
| Mike Moore | 4 September 1990 | 2 November 1990 | Labour
|
| Jim Bolger | 2 November 1990 | 8 December 1997 | National
|
| Jenny Shipley | 8 December 1997 | 5 December 1999 | National
|
| Helen Clark | 5 December 1999 | (present) | Labour
|