Rehabilitation workers are welcoming the banning of synthetic highs, but say it won't be the end of the drugs.
MPs last night voted 119 to one in favour of the Psychoactive Substances Bill, meaning drug manufacturers will now have to prove their products are safe before they can be sold.
The law change also imposes restrictions on where synthetic drugs can be sold and requires they can only be sold to people 18 or older.
Wellington's Te Menenga Pai Trust manager Carole Maraku says while she is pleased the Bill's gone through, there will inevitably be a black market for the drugs.
"Someone out there who knows they can make a dollar on this and doesn't actually care about the impact of what that drug does to somebody, they are going to look at ways of being able to sell them."
Only hours after the law was passed, a local board in Auckland has begun moves to ban legal highs from anywhere near its schools, kindergartens, churches and community halls.
The Manurewa Local Board has voted to ask Auckland Council to urgently draft a policy enabling it to ban the sale of legal highs within a one kilometre radius of key community areas.
Local board member Simeon Brown says he doesn't believe the drugs should be sold even if they are safe.
"I want to have them driven out of our community, that's what the community's been saying to us consistently and that's what we've responded with."