O'Neill's first journalism career was at the Waterford News & Star in 1982; he then worked for the Cork Examiner in 1989.
[2] He served as Deputy Editor of the newspaper under both Geraldine Kennedy and Kevin O'Sullivan.
[3] On 5 April 2017, the Irish Times Trust announced that O'Neill would be replacing O'Sullivan as the newspaper's editor.
[4] O'Neill was born in either 1964 or 1965, and brought up in Waterford by his parents Paddy and Josie (née Larkin).
[5] His father was editor of the Waterford News & Star, while his mother's family owned a bar and grocery store in Enniscorthy, County Wexford.