The Historical Institutional Abuse Inquiry ran for four years, examining allegations of abuse in 22 homes and other residential institutions in Northern Ireland.
The institutions were run by the religious orders, as well as churches, the State and charities.
Inquiry chair Sir Anthony Hart found shocking levels of sexual, physical and emotional abuse across the period 1922 to 1995.
He also found evidence of “systemic failings”.
Sir Anthony made a series of recommendations in 2017 including that a redress scheme be set up as a “matter of urgency”.
He said the minimum payout should be £7,500 with the maximum amount given to those who had experienced severe levels of abuse as well as being transported to Australia in a controversial migrant scheme.
The compensation scheme opened in 2020.
By the end of November 2021, more than £26 million had been paid out to survivors.
Fiona Ryan was appointed in 2020 as Commissioner for Survivors of Institutional Childhood Abuse (Cosica) fulfilling another one of the recommendations.
Sir Anthony also recommended a public apology be made to survivors, which is set to be delivered in the Stormont Assembly on Friday.
The final recommendation, which remains outstanding, is the creation of a suitable physical memorial sited within Parliament Buildings or the Stormont estate.
