Dermot Ryan will take up the position of General Secretary at the Financial Services Union in the near future.
Mr Ryan will take over from Larry Broderick who announced his intention in November to retire after working for the union for more than 30 years. He has been its general secretary for the past 16 years.
Dermot Ryan returns to Ireland from Australia where, most recently, he was head of external affairs for Amnesty International Australia.
Before that he worked as chief of staff of the Transport Workers Union of Australia (TWU).