London, England - The Church of England will launch a review into child abuse in the church, the Archbishop of Canterbury has said.
Three people have been jailed since April for crimes dating back decades. In each instance, the church had been alerted but failed to take action.
Dr Rowan Williams apologised for the way things had happened in the past and said policy had now changed.
He told the BBC that there would also be a review of recent cases to ensure it had stamped out abuse in the church.
Victims in child abuse cases involving Church of England officials have been calling for further investigations into possible similar offences in the past.
The victims had warned that the usual vetting checks will not uncover historic cases if the church covered up previous abuse.
Professional advice
Asked how he could be sure that no abusers remained in the church, Dr Williams said there had been three "substantial" meetings in Leicestershire on the issue this week.
He told BBC Radio 4's Today programme: "What we have agreed to do is to take advice from the church's central safeguarding group, which is the child protection clearing group, on how best to conduct a review.
"We don't just want to look good and so we need to have the best professional advice on how to review these historic cases."
The Bishop of Manchester has ordered an independent investigation into the files of 850 members of the clergy.
The Right Reverend Nigel McCulloch is to appoint a lawyer to make sure none of the files contain outstanding child protection issues.
Dr Williams said he approved of the bishop's investigation and reiterated that a similar review would be carried out across the country.
Prompt reporting
He insisted that policy had changed since the recent batch of cases, which date back to the 70s and 80s.
"I fully acknowledge that errors were made in the period that's being discussed - certainly before '95, practice was very variable, very uneven and often not very competent or well informed about the law or best practice.
"We now have, from '95 onwards, a very clear policy about this, which involves avoiding some of these very inadequate responses. We look after it ourselves - prompt reporting to police and social services is built into this. "
One abuse survivor told the BBC that the church never asked her what had happened or how long the abuse had continued. Instead she was told to forgive her abuser.
She said: "At that stage I felt I had to please people. I would do what people wanted me to do.
"I tried to pretend that nothing had happened. It was not until much later that just by saying 'I forgive you', which is what the church told me to do, it was still eating away at me.
"It had not been dealt with. It has had a major effect on the rest of my life."
Legal procedures
Derrick Norris, a churchwarden at Emmanuel Church in Northampton was sentenced to eight-and-a-half years in prison last month for raping and abusing a young girl and sexually abusing a teenage boy.
The other recent cases involved the Reverend David Smith, 52, of St John's Road, Clevedon, Somerset, who was jailed for sexually abusing six boys over a 30-year period, and former choirmaster Peter Halliday, 61, from Farnborough, Hants, who was sent to prison for sex offences against boys in the 1980s.
Halliday admitted the abuse 17 years ago, but left the Church quietly on condition he had no further contact with children.
After the Halliday trial, Dr Williams said any case in which the church failed to prove itself a safe place for children was "deplorable".
"The principle that the welfare of the child must always take priority has sometimes been misunderstood to mean that a child should not be put through the distress of public legal procedures," he said.