Retired Judge Sir Anthony Hart is to chair Northern Ireland's official inquiry into the abuse of children living in residential care back to 1945.
Organisations who ran the institutions will face pressure to explain the treatment of young people over the course of five decades.
They could include Catholic religious orders, state and voluntary groups. There will be an acknowledgement forum for victims to tell their stories and an inquisitorial investigation of evidence and questioning of witnesses.
Northern Ireland First Minister Peter Robinson said: "We are very pleased that Sir Anthony Hart has agreed to lead this inquiry and we know that he will be unflinching in his pursuit of the truth and scrupulous in his analysis of the evidence."
The inquiry is expected to begin its work in the autumn and will report in approximately three years' time. Its findings and recommendations will then be considered by Stormont's ministerial Executive, which will decide the way forward.
The inquiry will assess whether there were systemic failings by the state or institutions in their duties towards children under 18 for whom they provided residential care between 1945 and 1995.
Mr Robinson added: "Many people have called for this inquiry. I am confident that the scope and nature of this process is robust, will provide a thorough examination of what happened and will get to the truth."
The appointment of Sir Anthony follows lengthy judicial examinations of claims of abuse in the Irish Republic. Deputy First Minister Martin McGuinness said the inquiry will include a confidential "acknowledgement forum" in which victims and survivors can recount their childhood experiences in institutions.
Beverley Clarke, Norah Gibbons, Dave Marshall QPM, and Tom Shaw CBE will be forum panel members. Each has unique personal experience of investigating child abuse.
Mr McGuinness said: "They will listen to and acknowledge the testimony of victims and their work will result in a report about the children's experiences."He added: "We will introduce legislation shortly to ensure that the inquiry has the powers, flexibility and protections it needs to complete its work."