The country's largest problem gambling service says it will shortly start court proceedings against the Ministry of Health over the loss of most of its funding.
The ministry told the Problem Gambling Foundation in March the contract for three-quarters of its services would end in June.
Foundation chief executive Graeme Ramsey said many of its 63 staff stand to lose their jobs and the aim of the legal action is to delay handing the service over to the ministry's preferred new provider, the Salvation Army.
He said documents from the ministry acquired through the Official Information Act had not shed light on the reasons for the decision.
Mr Ramsey said the foundation believed there was a case to be heard because if the change was implemented, it would be irreversible.
But the foundation needed time, he said, to examine the grounds on which the decision was made.
Mr Ramsey said public law specialist Mai Chen will represent the foundation in court.