The Prison Ombudsman published a damning report on Maghaberry.
The senior management team at Northern Ireland's largest prison is to be replaced following a review into the death of a prisoner.
But the governor and deputy governor at Maghaberry will not face disciplinary action over the death of Colin Bell.
Bell who was serving a life sentence for murder, hanged himself in 2008.
An earlier report found some staff who were supposed to be monitoring him were lying in bed watching television while they were supposed to be on duty.
Bell, who had a history of self-harm, was on suicide watch and was meant to be monitored every 15 minutes.
The Prisoner Ombudsman Pauline McCabe published a damning report on the regime at the prison earlier this year.
She listed a catalogue of failings and made 44 recommendations for change.
One of them was that the governor and deputy governor should face a disciplinary investigation.
That was rejected on Tuesday in a report produced by a government-appointed review team.
However it said a new senior management team, led by a governor from outside Northern Ireland, should be appointed as soon as possible.
Staff should have monitored Colin Bell because of his history of self-harming
The report also said that Colin Bell was "the victim of an insidious subculture that allowed delinquent behaviour by some junior staff, much of it undetectable because of their isolation from unannounced supervisory visits."
It said the whole of the Northern Ireland Prison Service (NIPS) requires "significant cultural change" which will require "extraordinary leadership at all levels."
The Prison's Minister Paul Goggins said that while NIPS had made efforts to modernise the review team had found "systemic problems."
"The review team highlight the need to bring in new talent from outside NIPS, as well as developing existing managers. They stress that commitment and resilience are required to implement their recommendations.
"The report emphasises the need for improved performance management and accountability.
"It restates some other key messages - rehabilitation and resettlement are integral to the work of the Service, clarity in the respective roles of establishments and headquarters is important, and achieving the right relationship between management and the trade unions is essential. "
Robin Masefield, the NIPS Director said the report was "constructive" and that it was important to see it as "an opportunity rather than a threat."
The ombudsman welcomed the report saying the actions proposed will be "very helpful in meeting the current and future challenges facing the Prison Service."