The Local Government Commission is to investigate a possible amalgamation of Nelson City Council and Tasman District Council.
The commission has accepted a petition from the region signed by 10% of voters from each area.
A possible merger has long been touted by Nelson councillors but opposed by many in Tasman.
The man behind the latest succcessful move, Nelson councillor Aldo Miccio, says a Local Government Commission investigation will take the emotion out of the debate.
If amalgamation is recommended, he says, it could be put to a referendum next year.
