| 1948-1954 | Studied Chemistry at the University College Dublin, National University of Ireland |
| 1955-1956 | Postdoctoral Fellow at the University of California, Los Angeles |
| 1956-1978 | Lecturer in Organic Chemistry, University College Dublin |
| 1971 | Research Fellow: Kunglia Tekniska Högskolän, Stockholm, Sweden |
| 1978-1980 | Leader of the delegation to the CSCE meetings in Bonn and Hamburg to promote security and co-operation in Europe |
| 1978-1983 | Member of the National Board for Science and Technology (NBST) |
| 1979-1996 | Professor of Phytochemistry, University College Dublin |
| 1982-1984 | President of the Phytochemical Society of Europe |
| 1984 | Irish representative on the EEC Committee for Training in Science and Technology (ACPM-STT) |
| 1985-1990 | Chairman, European Science Research Councils, (ESRC) |
| 1989-1992 | Vice-Chairman of the Board of Governors and Guardians of the National Gallery of Ireland |
| President of the Royal Dublin Society |
| 1990-1991 | Senior Vice-President, Royal Irish Academy |
| 1994 | Chairman, National Education Convention |
| 1994-1996 | President, Institute of Chemistry of Ireland |
| 1997-1999 | Council Member, Royal Society of Chemistry |
| 1997-1998 | Senior Vice-President, Royal Irish Academy |
| 1998-2000 | Vice-President and Member of the Executive Council of the European Science Foundation |
| 1998 | Chairman, INTAS Evaluation group |
| Chairman, INCO 5 year evaluation |
| Chairman, Evaluation Committee OECD Programme "Megascience Forum" |
| 2001-2005 | Chairman, Commission for Assisted Human Reproduction |
| 2005 | Member of the Board of National Museum of Ireland and Chair of the Audit Committee |
| 2006 | Member of Council Royal Irish Academy |
