Brendan O'Brien reported on Northern Ireland as RTÉ's senior current affairs reporter beginning in 1974, and he made three major documentaries about the IRA. He won many awards for investigative journalism, including European Journalist of the Year 1998 and the Amnesty International Award 2001. Since retiring from RTÉ he has lectured extensively on the Northern Irish conflict and peace process.

He is the author of The Story of Ireland, a children's book illustrated by Cartoon Saloon; The Long War: The IRA and Sinn Féin; and the revised and updated edition of A Short History of Ireland (by the late Breandán
Ó hEithir). He lives in Wicklow with his family.