A billion dollars is how much the Government says it will bank from its crackdown on beneficiaries that kicks in today.
Social Development Minister Paula Bennett's "fundamentally different" welfare reforms aim to shake up the country's welfare system.
In a raft of changes, job seekers now risk having their benefits cut if they do not stop using drugs.
In other changes, the Domestic Purposes Benefit, the Sickness Benefit and the Unemployment Benefit no longer exist. The Sickness Benefit has been replaced with a Supported Living Payment.
"There are significant changes for hundreds of thousands of New Zealanders today," said Ms Bennett.
"The benefit savings could be anywhere between a billion dollars and 1.6 billion."
Deputy Prime Minister Bill English told TV ONE's Breakfast that too often the Government's put money into people's bank accounts and left them to it.
"The Government is going to be much more active in supporting people back into work.
"What we are trying to do here is move into a pretty much one on one approach where WINZ has a good understanding of what the needs of individual beneficiaries have and the barriers to work. "
He admitted that there will be instances where the approach does not work.
But he said today is day one of the shift in focus of the welfare system to what the Government call the investment approach.
"That is putting more money and more support behind people who are able to work," Mr English said.
Ms Bennett said rates will remain unchanged and there will be extra support for those who want to work but need more help to get them ready.
But Auckland Action Against Poverty (AAAP) said these "reforms" will have a brutal impact on hundreds of thousands of children and adults who are dependent on state survival.
"This is not about getting people into decent work - it's not about job creation. It's about cutting costs by pushing vulnerable people off the books," said Sarah Thompson from AAAP.
"Work and Income's gate-keeping culture has seen a growing number of people being incorrectly denied both financial support and the right to even apply for various supports."
Other obligations for parents on benefits
To ensure their children attend 15 hours a week of Early Childhood Education from 3-5yrs.
Make sure their children attend school from age five or six.
Enrol with a Primary Health Organisation, Integrated Family Health Centre or GP.
And children complete WellChild/Tamariki Ora checks.