The Roman Catholic Archbishop of Birmingham told an inquiry the archdiocese will "learn from mistakes" over how child sex abuse allegations were handled.
Most Reverend Bernard Longley said he "could not rule out every danger, but would use best practises to safeguard children and vulnerable adults."
Archbishop Longley also said he wants victims of abuse to talk to him.
He gave evidence at the Independent Inquiry into Child Sexual Abuse.
An inquiry has this week explored Birmingham Archdiocese' response to allegations made against four priests, including Father John Tolkien, son of novelist JRR Tolkien, after these were not reported by the church for decades.
Giving evidence on Friday, Archbishop Longley told the inquiry in London: "It is impossible to rule out any danger in every circumstance, but we continue to put in place the best practises in order to safeguard children and vulnerable adults."
He added: "I think there is still room for a lot of improvement.
"I know that within this week there are two or three examples that I can think of that are mistakes - some of which have been acknowledged from which we can learn.
"I hope that the inquiry will, in its recommendations to the archdiocese, enable us to."
Archbishop Longley said he started speaking to victims after former Roman Catholic priest Alexander Bede Walsh, from Staffordshire, was jailed for 22 years for sexually abusing eight boys at churches and children's homes in Coventry, Staffordshire and Warwickshire in the 1970s and 1990s.
He said: "I learnt something of the trauma they had experienced and an insight into the way in which the circumstances of abuse had evolved.
"My door is open to victims and survivors of abuse."
- 12 November 2018
- 20 July 2003