The Wales office of the Independent Inquiry into Child Sexual Abuse is to be officially opened today.
The inquiry will investigate allegations of historic child abuse at public bodies and other institutions across England and Wales.
Professor Alexis Jay, chair of the probe, will attend a launch event in Cardiff.
It will also mark the start of the inquiry's "truth project" in Wales, through which victims and survivors of abuse can share their experiences.
Last week, Professor Jay, who is the inquiry's fourth chair, unveiled her strategy to complete most of its work by 2020.
The inquiry has been mired in controversy since it was launched in 2014.