Health authorities say the first person to be charged under a new law with illegally selling synthetic highs could be jailed for up to two years.
A Hamilton man is facing two charges under the Psychoactive Substances Act, which came into effect last month.
He is accused of possessing and selling or supplying synthetic cannabis products that were not approved.
Police say they were being sold from a dairy, which is not allowed under the new law - 1200 packets were seized.
Waikato District Health Board Health protection adviser Nick Young said dairy owners were given extensive education about the change.
He says the charges should send a strong message to retailers who are thinking about flouting the new law.
Executive director of the Drug Foundation, Ross Bell, is welcoming the speed with which the charges were laid.
"Communities have always wanted these products out of dairies - the law did that from day one."
The accused is due in Hamilton District Court on 3 September.
The legal high industry says there are regional inconsistencies with how the new legislation is being enforced.
Most of the country's legal high companies are represented by the Star Trust.
Spokesperson Grant Hall said he is pleased that police in Hamilton acted because he has struggled to have his complaints followed up elsewhere.
He said the trust approached police in Tauranga three times about a retailer it believed was flouting the new law.
The organisation eventually went to the district health board to have it closed.