The legal names of government departments are kept in schedules to public-service Acts. Every amendment records the name, date and instrument that changed it. I collected the changes since 1988, along with the original 1912, 1988 and 1989 lists, then coded each name by form, subject and language. The result shows what governments choose to call the work of the state, and how that vocabulary changes.
In 1885 the law called them Hospital and Charitable Aid Boards. In 1983 they became Area Health Boards. On 1 July 1993, 23 Crown Health Enterprises replaced them and were expected to make a profit. Parliament removed enterprise from the name in 1998. District Health Boards arrived in 2001, with elected members restored. In 2022 the boards merged into Health New Zealand, Te Whatu Ora. In 2026 Parliament put the English name first.
The sequence is a short history of health policy: charity, regional planning, commercial discipline, elected local boards, centralisation and the order of the two languages. Each change has an Act or Order in Council behind it.
The Public Service Act 1912 had no list. It defined the service as everything done for the Crown, minus the exceptions it named: judges, magistrates, the Defence Force, the police, anyone paid by fees, and the whole Government Railway service. The State Sector Act 1988 worked the other way and simply listed the departments, 37 of them as at 1 April 1988. Lands. Forestry. Energy. Printing. Insurance. Most names simply said what the department did.
The list lasted twenty months before Parliament replaced the whole schedule. In December 1989, the Department of Education became the Ministry of Education, Trade and Industry became Commerce, and Māori Affairs split in two. This reflected the machinery-of-government reforms: more ministries advising ministers, with operational work separated out. The 1989 list held 41 names, the largest in the dataset. Ministries have been gaining on departments ever since.
The corporatisation statutes made the change unusually literal. State-owned companies needed company names, so Limited entered the record in 1990 with New Zealand Rail Limited. Hospitals followed in 1993 as Crown Health Enterprises. Between June 1990 and May 1993, six trading arms left the department list. The Ministry of Energy went under an Act that said exactly what it did: the Ministry of Energy (Abolition) Act 1989.
Rail shows the full round trip. Sold whole in 1993, renamed Tranz Rail by its buyers in 1995, the tracks bought back for a dollar in 2004 and the trains for $665 million in 2008. The operation now trades as KiwiRail, a brand with no organisational noun in it.
The splits of the era mostly folded back. Agriculture and Fisheries, separated in 1995, were one ministry again by 2011. Justice was cut three ways in 1995; Courts was back inside by 2003. Child, Youth and Family left Social Welfare in 1999, merged into Social Development in 2006, and was cut out again in 2017.
The Department of Social Welfare became the Ministry of Social Policy in 1999 and the Ministry of Social Development in 2001. The schedule missed the middle name because only Parliament could amend it at the time and no Act was passed. The three names describe the same organisation differently: welfare as provision, policy as advice and development as an outcome.
The same shift appears across the dataset. The 1988 baseline had 46 names based on function and none based on aspiration. Of the names first seen since 2010, 15 describe a function, 13 a client group and 7 an aspiration. Health and Labour name the work. Innovation, Investment and Development name a result.
Even the prepositions changed. On 1 December 2015 two ministries changed theirs on one day: of Pacific Island Affairs to for Pacific Peoples, of Women's Affairs to for Women. The new wording made advocacy more explicit. In 2017 the new children's ministry was named the Ministry for Vulnerable Children, Oranga Tamariki. Vulnerable lasted a year before it was removed for labelling the children it served.
Parliament gave a department a te reo name in 1991. Section 4 of the Ministry of Māori Development Act says the Ministry's name in Māori is Te Puni Kōkiri, but the schedule went on printing Ministry of Māori Development for 28 years. The first dual name reached the list itself on 6 May 2003, when the National Library Department became the National Library of New Zealand Te Puna Mātauranga o Aotearoa. 9 more have arrived since 2010.
The order of the languages is set by instrument, and it has moved with the government. Oranga Tamariki put te reo in front in January 2018, three months after Labour took office. From 2024 the instruments run English-first, and in 2026 Parliament amended the Pae Ora (Healthy Futures) Act 2022 so that its own title now reads Healthy Futures (Pae Ora).
Recent instruments have reversed several names introduced by the previous government. The Social Wellbeing Agency became the Social Investment Agency in July 2024. The Ministry for Disabled People became the Ministry of Disabled People that December. In 2025, the Office for Māori Crown Relations, Te Arawhiti, became the Office of Treaty Settlements and Takutai Moana. In 2026, the Ministry for the Environment was folded into the Ministry for Cities, Environment, Regions, and Transport, the longest name in the dataset. Together, the changes replace wellbeing, for, Crown relations and te reo-first naming with investment, of, settlements and English-first naming.
Labour governments made 34 of the 76 reorganisations in this dataset and National-led governments 42, which is 1.9 a year against 2.0 after allowing for time in office. The frequency is almost identical, while the vocabulary changes: te reo moved to the front of names three months after the 2017 change of government, and English-first instruments began within a year of the 2023 change. There are exceptions. The 2015 switch from of to for came from a National government, and both parties used Limited during the corporatisation era.
The churn is not evenly distributed. 13 of the 41 departments of 1989 reached 2020 unchanged, The Treasury, Inland Revenue, Defence, Internal Affairs, Conservation and Crown Law among them. The churn concentrates in the portfolios the parties fight over: welfare, children, health and Māori affairs. Names in less contested portfolios are more likely to stay put.
Not every change is ideological. Company law explains the Limited names: an SOE has to be named like a company. It does not explain Welfare becoming Development. Some words may simply be imported fashion; agencies, authorities and Development appeared across the English-speaking world at about the same time. Names alone cannot separate fashion from political preference, or prove motive. They can show which words changed, when and under which government.
Bodies scheduled under the public service Acts in that year: departments, and from the 2010s the departmental agencies and executive boards too. The record here starts at 1 April 1988.
The dataset covers every organisation listed as a department in the schedules to the State Sector Act 1988 and the Public Service Act 2020, plus bodies created by restructuring them. The schedules' amendment notes record insertions and repeals, with dates and legal instruments. The 1912, 1988 and 1989 starting lists come from the Acts as originally passed. Each name is coded by form, subject and language. The rules and data are downloadable below so the classifications can be checked.
There are gaps. Membership between 1912 and 1988 has not yet been reconstructed. Dates for a handful of 1990s organisations still need to be confirmed, and some successor chains rely on secondary sources until the Gazette can be checked. The date the Post Office left the Public Service is also unresolved: it was included in 1912 and abolished in 1987, but I have not yet checked every statute in between. If you find an error or a missing strand, write to will@willedmonds.com and the corrections list below will record the fix.
The consolidated Acts keep the note recording when an organisation left the list, but sometimes drop the note recording when it arrived. That means an abolished body may have a firm end date and an uncertain start date. Where the same section removed one entry and inserted its replacement, I recovered the arrival from that repeal and marked it in the data. The National Library is the important example: the surviving notes point to its 2011 repeal, while the instrument that created the dual name dates it to 6 May 2003.
Every correction is listed here with the date it was made and what it changed.
9 August 2026. Added analysis by governing party, discussion of alternative explanations and a new figure. Added 14 events from the December 1989 replacement schedule, raising the reorganisation count from 62 to 76.
9 August 2026, later. Shortened the essay and moved the unresolved Post Office question to the method. No numbers changed.