ACT says it would aim to halve the more than 6000 staff at the Ministry of Business, Innovation and Employment (MBIE).
It would also immediately shut down work on several Government projects if elected to Government, saying this could save more than $1 billion.
The projects include Three Waters, fees-free tertiary study, growth and development grants, the provincial growth fund, Auckland Light Rail, Callaghan Innovation, Workforce Development Councils, Industry Transformation Plans, RMA reform, He Waka Eke Noa, MBIE's "Just transitions" unit and regional skills leadership groups, income insurance, fair pay agreements, space policy, the game development sector rebate, the major events fund, R&D grants groups Te Ara Paerangi and Vision Mātauranga, and any screen sector supports.
Many of these were based at MBIE and party leader David Seymour said new ministers would issue Stop Work notices to chief executives on day one.
"Those doing the work will be told to down tools, then they'll be made redundant, or maybe redeployed, but it is better to send them home than let them keep doing damage to New Zealand," he said.
"Other Stop Work Notices would cover, for example, the Ministry of Education's curriculum refresh and Let's Get Wellington Moving."
This would be followed by requiring outlines of all the teams within ministries and departments, their activities and expenditure.
"Ministers will then identify teams and activities they require departments to cut because they aren't providing value for taxpayers or because they overlap with functions that exist elsewhere in the bureaucracy."
MBIE's staffing had grown from more than 3700 to more than 6100 since mid-2018, he said, and spent "an extraordinary amount of money on policy advice".
"They've increased by 64 percent just in the last six years without doing any better, what they should have been doing is increasing their productivity over that time," he said.
"They should be able to achieve 2017 levels of performance with fewer people, and if you think about a reasonable rate of productivity growth over six years they should actually be down closer to 50 percent of what they have now."
He rejected suggestions there would be a need for workers to develop, for example, the National-ACT alternative to the three waters programme.
"Nope, they could walk out, switch out the lights, transfer the assets back to the councils who had built them up and governed them for many years and nobody would notice except for those people who had been high on the hog in three waters salaries. The only real task would be redeploying the leases of the offices and haggling down the redundancy payments for people who've had it too good too long."
When asked if National would support this approach, Seymour suggested it was more a matter of necessity than policy.
"I think what National will have to listen to is economic reality," he said. "It's not so much a matter of what do ACT think or what do National think, it's going to be a question of what do the numbers say and when do we start making New Zealand financially sustainable again."
He was not worried about losing public sector votes, either.
"I expect that we will get more votes from within the bureaucracy because there will be people in the bureaucracy who know that their colleagues aren't doing anything productive - and they'll vote for ACT hoping that their colleagues will get fired."
RNZ
