New Zealand's only private prison will begin housing inmates from Wednesday but concern has already been expressed about staffing levels.
British company Serco is running the new Mount Eden jail for at least the next six years.
The company's contract with the Government doesn't stipulate minimum staffing and the main prison guards union is worried the staff-to-inmate ratio won't be right.
Corrections Association president Bevan Hanlon says the approximately 960 inmates were handled by 427 prison guards under public management but that number has dropped to 200 under private management.
Serco rejects the figures, though is refusing to say exactly how many staff it has for reasons of security and commercial sensitivity.
