The Catholic Bishop of Raphoe has admitted that "horrific acts of child abuse" occurred in the diocese and that "very poor judgements and mistakes" have been made.
Bishop Phillip Boyce gave the statement as a review into how child protection measures have changed since 1975 in six Catholic dioceses were released on Wednesday.
The audit was was conducted by National Board for Safeguarding Children in the Catholic Church (NBSCCC).
The report of events in the Diocese of Raphoe in County Donegal has been much anticipated following allegations that priests sexually abused children over a 36-year-period.
The audits of Derry, Dromore, Tuam, Ardagh, Kilmore and Clonmacnoise will also be published by their perspective dioceses today.
"During the past decades there have been very poor judgments and mistakes made," said Bishop Philip Boyce in a statement.
"There were horrific acts of abuse of children by individual priests, that should never have happened, and if suspected should have been dealt with immediately in the appropriate manner."
The Raphoe report draws attention to "significant errors of judgement" by "successive bishops."
The 23-page report published today shows 52 complaints were made against 14 priests during January 1975 and August 2010. The most notorious offender, Father Greene, was sentenced to 12 years in prison in 1999 for abusing over 26 boys over 20 years. He is the only priest who is named in the report.
There are eight priests who have had allegations made against them whilst at Raphoe who are now "Out of Ministry" or have left the priesthood.
Overall, four priests of the diocese have been convicted of having committed an offence or offences against a child or young person since January 1975.
"We are truly sorry for the terrible deeds that have been inflicted on so many by a small minority of priests," the statement from Bishop Boyce continued.
"We offer our humble apologies once more and seek their forgiveness for the dreadful harm that has been done to them, their families and friends.
"Insufficient emphasis was placed on the needs of victims, often in the misguided attempt to protect the reputation of the Church", he said.
"This review has concluded that the diocese now has a robust safeguarding policy and procedure in place for safeguarding children."
A separate audit of child protection practices in the Diocese of Dromore has revealed 35 allegations of abuse have been made against ten priests dating back over 30 years.
The audit on theArchdioceses of Tuam says allegations were made against 18 priests of the diocese since 1975. Two of the priests have been convicted; ten of the 18 are now deceased, including one of the convicted.
The dioceses of Ardagh and Clonmacnoise, and Kilmore are also expected to publish reports on Wednesday.
Bishop Boyce intends to make renewed contact with those victims of child abuse by the clergy to make sure their needs for appropriate counselling, spiritual support or word of apology are adequately met.