Having delivered the biggest election victory her center-left Labour Party has seen in half a century, she no longer needs the support of other parties to govern.
However, coalitions are the norm in the nation of nearly five million people, as parties look to build consensus.
The Greens are obliged to back the government over decisions made in their portfolios but are otherwise entitled to take a different position to Labour.
Prior to the October election, the Labour Party was in a governing coalition also with the Greens and New Zealand First.
JACINDA ARDERN: You know, we all know the numbers. We've made our view clear. And [INAUDIBLE], obviously, you would have heard some introductory--
In this agreement, there is agreement from the Green Party not to oppose the government on important votes like confidence and supply, to support us in procedural motions and [INAUDIBLE].
All of that gives that extra surety for us to be able to govern with the mandate that New Zealand has given us. So there are areas I think we need to make sure that we have delivered well.
This agreement is unlike any other. It does not require consensus to be formed. It allows the parties to take their own positions on issues where that is important, but offers to work together in other areas too.
And start a coordinated hand shake.
JACINDA ARDERN: I'll start on the outer.
- Very good.
JACINDA ARDERN: Thank you. We'll go there. And then I'll go there.