Liam O'Mahony joined CRH in 1971. He has held senior management positions including Chief Operating Officer of the United States operations and Managing Director, Republic of Ireland and UK Group companies. He joined the CRH Board in 1992, was appointed Chief Executive, Oldcastle, Inc. in November 1994 and became Group Chief Executive in January 2000. He is a member of The Irish Management Institute Council and of the Harvard Business School European Advisory Board.