In her speech, Ardern greeted those gathered in Māori and said she was back to be held to account, as she promised when she spoke at Te Whare Runanga last year.
Watch Jacinda Ardern and Winston Peters' press conference:
Ardern outlined what the Government had done that would improve life for Māori, such as reducing unemployment, increasing benefits and the Working for Families package.
With each of the achievements she mentioned though, Ardern emphasised "there is still more to do".
NZ First leader and Deputy Prime Minister Winston Peters said the Government was setting about dealing with some "enormously" difficult issues but it was coming equipped with the money to do that.
"We are the only ones who can do it."
MPs arrive as one group for first time
Earlier, the official party of MPs arrived at Te Whare Runanga as a single group for the first time, led by Labour MP Peeni Henare.
National leader Simon Bridges answered the challenge and picked up the wero.
The opening speaker, Bernard Henare, brought up the fraught issue of the Ngapuhi mandate, saying that even as iwi fought among themselves, people were living in poverty.
The speeches in te reo were translated into earpieces. It is the first time the technology has been used, and allowing a two-way conversation between Māori and the Crown.
The translator struggled to keep up with the speech by NZ First MP and Regional Economic Development Minister Shane Jones.
Jones, who is known for his flowery oration, seemed beyond the capabilities of the translator attempt to covert it to English.
National's Nuk Korako spoke on behalf of his party. He acknowledged kuia Titewhai Harawira who, like last year, was seated next to Ardern.
Bridges, who is Māori, opened his speech in Māori.
The dignitaries' powhiri, upper marae Waitangi. Photo / Michael Craig
He joked that Ardern's baby Neve, sitting quietly on father Clarke Gayford's lap nearby, was the best-behaved baby there.
"Give it time Prime Minister," he joked.
Bridges singled out Crown Māori Relations Minister Kelvin Davis for his work in bringing dignity to the event.
He said he agreed with Ardern's view that this was the year of delivery.