Front line Corrections staff will not be among the 140 people to lose their jobs if a proposal goes ahead to bring prisons, rehabilitation and probation services together.
Under the plan the services would be combined into one team that would be responsible for daily management and rehabilitation of all offenders across the country.
While it would see changes in management structure at head office and in some regional offices, front line staff would not be affected, said Department of Corrections chief executive Ray Smith.
The changes were aimed at making communities safer by "lifting our performance'' said Mr Smith, who has developed it over the last six months.
"The proposed new structure will enable us to work together to co-ordinate the management of each offender at every stage and address the underlying causes of their offending.''
Under the existing system, prisons, community probation and rehabilitation and reintegration each has its own processes, infrastructure and staff.
"This creates replication of work, is inefficient and has resulted in an overly layered structure,'' Mr Smith said.
The existing system was inefficient and did not give senior managers the accountability or authority they need to make decisions locally, he said.
"The proposed structure would see one combined service group established in each region and a proposed fourth region created in the lower North Island.''
Following a consultation process, recruitment and re-assignment were expected to to take place in June and July, with staff starting new roles from August this year.
The proposed structure will save $10 million in employee costs compared to the 2012/13 financial year, said a Corrections statement.
Consultation with affected staff started today