Legislation cutting the number of Stormont departments from 12 to nine has cleared its final hurdle in the Assembly.
While the DUP said it would create a leaner and more efficient government, the SDLP claimed it could lead to paralysis as the new bodies took time to bed in.
The number of offices will reduce after the May elections under the Departments Bill, a pledge of the Fresh Start Agreement, which passed its final stage on Tuesday.
Emma Pengelly, DUP junior minister in the Office of the First Minister and Deputy First Minister, said: “It shows our commitment to a leaner, more efficient structure of government here.
“This is a good day for government in Northern Ireland. This is a good day for a better way of doing business and it is a good day for delivery.”
West Belfast Assembly member Alex Attwood urged people to tread boldly but had words of caution.
He said there was a short term risk of “a degree of paralysis as those departments settle themselves and embed in the wider life of Government.
“There is a tendency within some management levels of government to err on the side of conservatism and caution.”
The new departments will be:
:: Agriculture, Environment and Rural Affairs.
:: Executive Office.
Meanwhile, Alliance Party MLA Chris Lyttle has hit out at other parties for not backing an Alliance amendment on separate legislation which would have seen the number of MLAs reduced in time for May’s election.
Under the Fresh Start Agreement, such a cutback will take place at the first election after May.
Mr Lyttle said he could not understand why other Executive parties did not want to see the change now.
“We are in the strange situation of the parties having agreed to this reduction already but while Alliance wants to see it carried out now, others are holding off until 2021. Why agree to do something but wait five years to implement it?
“Estimates are it would save the taxpayer around £2.2 million each year, or £11 million per Assembly term, in wages, expenses and office costs.
“That effectively means 75 more police officers or 90 more nurses each year. In a time of austerity, there is no need to potentially wait five years before that money is put back into the public purse.
“A population the size of Northern Ireland does not need a legislature as large as the one we currently have. It is disappointing other parties decided to act in self-preservation and not follow Alliance’s lead to carry out much-needed reform, while still ensuring representation for smaller parties.”