Carolyn Tremain just before finishing as chief executive of the Ministry of Business, Innovation and Employment. Photo / Mark Mitchell
Departing public sector leader Carolyn Tremain reflects on her career, including eight years as head of MBIE, with Audrey Young.
Carolyn Tremain doesn’t come across as a powerful public sector Mandarin because, as head of the MBIE mega ministry for eight years, her nature has not been to take a high profile.
But during her time at the helm of MBIE, the Ministry of Business, Innovation and Employment has grown in size and influence.
And Tremain believes there is value in having more big organisations in the public service, of the sort that Public Service Commissioner Sir Brian Roche has been talking about.
“I personally think across government, we need to ensure that we have scale,” she said at MBIE HQ in Wellington, in the old deco Defence building in Stout St.
“There are opportunities to have, to bring together agencies to build better scale and be more comprehensive in the approach to complex problems.”
Many of the problems facing New Zealand required multiple inputs from different organisations.
“And so the more they’re clustered together in like activities, I think the easier it is.”
Tremain finished on Friday at the ministry, which has 5880 staff, with responsibility for 19 ministerial portfolios, 17 regulatory systems, more than 115 acts, and monitors 25 Crown entities.
The portfolios are as diverse as Immigration, Tourism, Energy, Space, Economic Development, Building and Construction, Resources and Workplace Relations. MBIE played a critical role in the Covid-19 pandemic, helping to manage lockdowns and run MIQ isolation facilities with the NZ Defence Force.
The diversity of the organisation is reflected in two of the highlights Tremain nominates in her time there.
The first was the role of the major events team in the Fifa Women’s World Cup, which New Zealand co-hosted with Australia in 2023.
“I think first of all, it probably came at a good time post-Covid. It was quite uplifting and communities really got behind some teams,” she said.
It had also left a legacy of improved play facilities.
“My granddaughter plays football, and I’m not sure necessarily that there would have been a lot of women’s teams for girls her age had we not had the profile of the Fifa World Cup.”
Another highlight was the decommissioning of the Tui oil field off the west coast of Taranaki between 2021 and 2025 after the permit operator had financial problems.
“We hadn’t done any decommissioning of anything of that scale,” said Tremain.
It had been a complex problem with no skills in New Zealand to undertake it.
“We had to bring in US and Singaporean companies to help us do that work. And no blueprints, at all. So the fact we got to the end of that under budget [for $293 million] was amazing.”
The most challenging times were in the aftermath of natural disasters, the Kaikoura 2016 earthquake, and the 2023 Auckland floods and Cyclone Gabrielle.
Covid, too, was a big challenge.
“Certainly, Covid was an extraordinary period. It was very easy to close the border and very difficult to open it again.”
Tremain is not retiring but wants to spend more time with family in Auckland, from where she has commuted for about 15 years.
The MBIE organisation was the baby of former Economic Development Minister Steven Joyce in the previous John Key-led Government.
It was billed as an amalgamation of agencies as a new business-facing department to take more effective leadership of New Zealand micro-economic policy agenda and decisions to improve productivity and competition.
The first chief executive in 2012 was David Smol, whose tenure focused on the actual amalgamation of the Ministry of Economic Development, the Department of Labour, the Ministry of Science and Innovation and the Department of Building and Housing.
Tremain had been head of Customs before joining MBIE in 2016. Her first job was in the Air Force in the accounting section. She then worked in the private sector in HR, in Farmers Trading, in Rix Consolidated Group, a metal and plastic manufacturing outfit, at Air New Zealand and the Inland Revenue Department.
She spent her early years in the rural community of Waiterimu near Huntly where her parents worked on a dairy farm, before moving to Hamilton where she went to Hamilton Girls’ High.
Her first break from HR came at Air NZ. She was asked by the then managing director, Jim McCrae, to step outside her comfort zone and work on a cost-reduction and revenue-growth exercise for a year, essentially a restructuring exercise.
She had several periods of her life when she was hesitant about doing particular jobs but was encouraged to do so by her bosses at the time, who were clearly more confident than she was that she was capable of it.
She was lured to the public service by David Butler, the then Commissioner of Inland Revenue, to work in corporate services.
“He has been a great mentor over many years.”
Then she was encouraged by another Commissioner, Bob Russell, to head IRD’s service delivery arm, with more than 4000 staff.
She would not have done that job without his encouragement, she said.
“It’s a mix of opportunity but encouragement to take that step to take that opportunity,” she said.
“I don’t put myself forward for things and so I try to be that encouraging voice for some of our women… but it’s also Māori and Pasifika people as well.”
She had a focus during her time at the top on having all levels of MBIE better reflect the community.
So how has MBIE weathered the new environment of constraint? She had been ready for it.
She said New Zealand went through economic cycles of expansion and contraction all the time across business.
“And I saw that in manufacturing, I saw that in retail, and I saw it in aviation.”
Some leaders had experienced all those cycles, and there was a degree of comfort in having a toolkit to help through the difficult times.
But sometimes the difficult times revealed “real stars” when they were given the opportunity to do things differently.
“Up until probably about 2022, we actually had a really long period of growth and good economic times. And it’s not surprising we’ve got a cycle of constraint now.
“But what I also know from my experience is we’ll have expansion again, too.”
MBIE had run a combination of voluntary redundancies and in excess of 40 restructurings across the organisation, taking out about 850 roles in 18 months.
Since a peak in December 2023, MBIE had reduced its workforce by 12.6%, to May 2025.
In one example, she said MBIE had consolidated elements of compliance work.
“Immigration had its own compliance, as did tenancy, as did the labour inspectorate people, but they were all, at essence, compliance people.”
They now worked together to optimise some of their techniques and management structures, but kept the frontline working in the numbers needed.
MBIE has grown significantly since it was established in 2012.
As of June 2017, shortly before the previous National Government left office, MBIE employed 3366.5 FTE, compared to 5879.6 FTE as of January 31, 2025, according to MBIE’s own figures.
That is growth of 2513 FTE or 74.6%.
Tremain said workforce growth was aligned to increased departmental baseline operating expenditure, which grew from $714.88 million in 2016-2017 to $1.3 billion in 2024 – 25 – an increase of 82%.
“The nature and size of MBIE workforce has changed over time in response to increased demand for system reform, and existing services and the addition of new services,” she said.
“Examples include the establishment of a New Zealand Government Procurement function, labour law reforms, the establishment of the New Zealand Space Agency, increased refugee quotas, the repatriation of visa processing services from offshore, the establishment of the Provincial Development Fund, expanded support for small business and increased demand for services such as tenancy, insolvency, dispute resolution and employment mediation.”
She said MBIE would continue to review the way it worked to make improvements in effectiveness and efficiency and look at opportunities in automation and artificial intelligence (AI).
In terms of size among public sector workforces, MBIE is the sixth largest, behind Health NZ at 80,500, Police at 15,770, Defence Force at 11,650, Corrections at 10,820, Ministry of Social Development at 9090, then MBIE at 5880.
Tremain has dealt with more ministers than most public service CEs because MBIE is responsible for so many portfolio areas.
She said a good minister had a clear work programme, and knew what their level of ambition was for the term that they held the portfolio.
“The more clarity we get, the easier it is for the policy teams to develop a work programme with the outcomes and impact that the minister and the Government of the day are actually seeking.
“The clearer the commissioning is from ministers, the easier it is for the public sector to respond.”
She hoped that she had left MBIE more “customer-focused, more agile and a bit more adaptive and realistic about the environment we’re operating in”.
In terms of her own leadership style, she said she was results-oriented, and she believed she was a calm and approachable leader.
“I think having clarity of purpose and being reasonably calm is a good mix because you have to know where you want to get to.
“You also have to deal with the inevitable bumps along the way, and if you overreact, sometimes that means people just stop telling you things…
“You might be spinning or thinking ‘Oh my God, how am I going to handle this?’ But at the end of the day, you always work your way through it.”
Audrey Young is the NZ Herald’s senior political correspondent. She was Political Journalist of the Year at the Voyager Media Awards in 2023, 2020 and 2018. She was political editor from 2003 to 2021.