Taranaki Māori health leaders say it will be a challenge to maintain local voices in a more centralised health system.
Health Minister Andrew Little has announced the 20 district health boards will be replaced by one new body, Health NZ, for the whole country.
There will also be a new Māori Health Authority to set policies for Māori health and to buy some health services directly.
The chief executive of community-based health provider Tui Ora, Hayden Wano, said the new structure would challenge iwi over how best to have their voice heard.
"There is a risk that with centralisation you lose the nuance of the way to make the right arrangements to meet local needs… That will be an interesting wero for iwi to represent what's happening on the ground."
The health review panel that prompted the shake-up had recommended only limited money for the Māori Health Authority, but the Government has sided with dissenting panellists who wanted it to control more spending.
Wano said having pūtea to buy services that best suit Māori would have significant impact, especially in community and public health.
"I think there'll be more focus on wellness and in prevention and early access... I'd like to think that they would take whanau approach, compared to a more individual approach."
The Government said the Māori Health Authority would have joint decision-making rights in national strategies, policies and plans, and would work with Health NZ on commissioning.
Taranaki DHB's chief advisor for Maori health, Ngawai Henare, welcomed what she said was a bold reform.
She said a key change would be that iwi partnership boards were to get power to approve local plans, rather than being advisory only.
Last year Taranaki's iwi board was given the ability make decisions locally, but it hadn't gone smoothly.
"We've already experienced some challenges giving effect to that, and I think the nationalisation of district health boards and the establishment of the Māori Health Authority nationally will give it the oomph it needs."
Henare said there were still a lot of details to work out and meetings had already been organised with the Ministry and the transitional Māori authority.
The chair of Taranaki's DHB iwi relationship board, Te Whare Punanga Kōrero, said the new Māori Health Authority would have niho (teeth) both in monitoring and in buying services that match Māori needs.
But Te Pahunga Davis said Taranaki Māori already have a strong voice in health, backed by iwi leadership, and that needed to continue in the new regional structure under Health NZ.
"That voice has got to be strong throughout otherwise there could be some diminishing effect… but it's such early days I would love to see heaps more detail."
Davis said stronger monitoring by the Māori Health Authority might prove even more important than its purchasing power, as much health data on Māori communities was missing.