Clerical abuse survivor Marie Collins says "every rotten apple" should be gotten rid of from the Catholic church.
She was speaking at The World Meeting of Families in Dublin's RDS.
The gathering heard there is denial within the Catholic church about the scale of clerical sex abuse.
There are calls for the Vatican to come up with a plan to address the issue, ahead of the arrival of Pope Francis tomorrow.
Ms Collins was abused by a priest as a child - she says survivors want more than just an apology from the Pontiff.
"Sadly still in the church, among clergy and laity, there are people who prefer to believe that all this is media conspiracy - just survivors trying to destroy the church - and they deny and defend.
Marie Collins addresses the World Meeting of Families event in the RDS, Dublin | Image: Leah Farrell/RollingNews.ie
"I hope that they will take their energies from defending the indefensible, accept the truth and instead of denial put their energy into bringing changes that are needed."
She also wants a zero-tolerance approach to those found to be perpetrating or covering up abuse.
"I think there is this fear of the domino effect: that if you start looking at bishops and they start being removed, how many more is it going to (take) down the line?
"I think it shouldn't matter: every one, every rotten apple should be got rid of - and it should happen now".