The inquiry aims to uncover the extend of child abuse in Scotland over the last 50 years
Church groups and a charity which ran children’s homes were among those who apologised as the first hearing of the Scottish child abuse inquiry took place.
The opening session in Edinburgh heard apologies from groups who said they "deplored that physical sexual abuses could occur".
They included Quarrier's, Daughters of Charity of St Vincent de Paul, Sisters of Nazareth, Good Shepherd Sisters, De La Salle Brothers and Christian Brothers.
More than 60 institutions, including several top private schools and church bodies, are being investigated.
Among those due to give evidence are Barnardo’s, Aberlour and the Church of Scotland’s social care arm, CrossReach.
The inquiry, which is being chaired by Lady Smith, is looking in detail at historical abuse of children in residential care.
The inquiry also has an important role to play in considering how we can best to prevent child abuse in the future - NSPCC
It is expected to report in late 2019 - four years after it was set up.
Lady Smith began the public hearings by acknowledging that many children in Scotland have been abused in residential care over the years.
She said: "They suffered some terrible treatment inflicted by those to whom their care was entrusted. That is a matter of grave concern.
"It is critically important that our community engages in facing up to the fact that children in care were wronged and failed in the past and to commit to seeing to it that children of today and of the future are safe.
"It's not easy to do that, for many it will be a painful process. But if we are to achieve real, substantial and lasting change for the better it has to be done."
John Scott QC, for the In Care Abuse Survivors group (Incas), said children had been "cruelly betrayed by those supposed to care for them".
He said the inquiry had come too late for those who have already died, but added: "It is not too late for at least some acknowledgement and accountability, not too late for some compensation, not too late for other survivors to come forward."
An NSPCC Scotland spokesperson said: "Victims of abuse in Scotland have waited too long to have their voices heard and we urge survivors to make contact with the inquiry to tell their story. We hope that the inquiry – when it reports – will succeed in addressing the full extent of any abuse that took place against vulnerable children in care.
“The inquiry also has an important role to play in considering how we can best to prevent child abuse in the future.”
Members of the public are welcome to attend the hearings although in some situations, the Chair may decide to hold hearings in private without the public present. There is no reserved seating in the public area and it is not necessary to notify the Inquiry of attendance in advance.
For those not able to attend hearings, a word-for-word transcript will be available for each hearing day on the inquiry website.
