A ministerial inquiry into mental health and addiction is not about tinkering, as significant change is needed in the sector, Health Minister David Clark says.
The six-person inquiry team will be led by the former Health and Disability Commissioner Ron Paterson and will hear public submissions around the country.
It will have the power to require reluctant witnesses to appear, but they would have the option to speak anonymously.
The inquiry will report back to the government by the end of October.
Dr Clark said that date had been set for a reason.
"It will give time to feed into a budget process. There are some who are of a view that a whole lot more funding is needed ...
"But there's also a view that some of the money is not being spent as well as it could be and it may be a matter of reallocating resource," he said.
The move to set up an inquiry is part of the Labour-led government's 100-day plan.
Dr Clark said from the start he had pushed for an inquiry that was very broad.
"That is to make sure we're getting a full picture not just a neat, tidy picture at the end which might be more convenient for a government that didn't want to do things.
"We do want to do things, we do want to see a better system so we're making it deliberately broad enough that we can actually look at that bigger picture."
Prime Minister Jacinda Ardern said mental health and addiction were issues for all New Zealanders.
"Most of us will know a friend or whānau member that has faced a mental health challenge in their lives.
"We have added addiction services to this review based on feedback during consultation.
"Mental health and addiction are often interlinked - they need to be considered alongside one another."
Ms Ardern said she wanted the inquiry to report back with a clear assessment of the current strengths and weaknesses of the community response to mental health, and of the response of the broader mental health system.
"Nothing is off the table, we all know we have a problem with mental health in this country and our suicide rate is shameful. It is well past time for us to do something about it."