Winchester College has apologised to victims of "terrible" abuse by the late Christian QC, John Smyth.
The evangelical barrister, who died in 2018, abused a number of former pupils at the boarding school from the mid-70s until 1982.
Smyth was chair of the Iwerne Trust during the same period. The evangelical charity ran religious holiday camps for boys, some of whom were students at Winchester College.
An independent review found that his abuse of boys from the school had been enabled by his "unfettered access to the college".
Smyth gained the trust of the boys by attending meetings of the Christian Forum, an evangelical group at the college which met on Sundays.
He was regularly invited to be a guest speaker but the report said that he would often sit in on other meetings.
The independent review was led by safeguarding experts Jan Pickles OBE and Genevieve Woods.
They found that although there were "some attempts by individual staff members to question his involvement or restrict his access to certain pupils", the college did not do enough to safeguard the boys in its care.
"Even basic safeguards which were common at the time for those in ministry or teaching roles, such as the use of interviews or references, were not utilised in relation to Smyth," the report said.
It added: "Smyth's unfettered access to the college allowed him to groom boys and created opportunities for abuse."
The college has "apologised unreservedly" to victims "for its part in their terrible experiences".
The abuse by Smyth came to light in a Channel 4 exposé in 2017, which found that he had physically and spiritually abused boys.
The findings prompted independent investigations by Scripture Union and the Church of England.
The Church of England's review is being carried out by Keith Makin and is due to be published later this year.