There's hope the Children's Rights Symposium in Wellington this week will lead to change.
International and local experts are attending the event, which falls on the 30th anniversary of the UN Convention on the Rights of the Child.
Children's Commissioner Andrew Becroft says people are now realising the importance of young people's voices.
"I think this has come at exactly the right time. I'm very optimistic that Government departments will take up this challenge and run with it."
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He wants children to have input into policy that affects them.
The symposium will look at issues across the care system, the criminal jurisdiction and Family Court.
Becroft says we need to get better at seeking out young voices.
"We've been a bit paternalistic in New Zealand - adults have all been children and young people themselves. They know what's best, but we haven't asked the children. Children's voices always add value."
He says the present Government has "made a good start", but will be challenged to do two main things.
"To meaningfully prioritise the welfare and best interests of children will be a primary consideration. But... also commit themselves to hearing children and young people, and seeking out their voices."
Becroft recently backed calls for the voting age to be lowered to 16.