| 1990 - 1993 |
Sub-Dean, Faculty of Science, NUS |
| 1993 - 1997 |
Vice-Dean, Faculty of Science, NUS |
| 1995 - 1997 |
Assistant Director of Research, NUS |
| 1995 - 1997 |
Coordinator, NUS-Japan Society for the Promotion of Science Program |
| 1996 - 1998 |
Co-Chairman, Medical Informatics Program, NUS |
| 1996 - 2000 |
Member, NUS Council |
| 1996 - 1997 |
Head, Department of Chemistry, NUS |
| 1997 - 2000 |
Dean, Faculty of Science, NUS |
| 1998 - 1999 |
Deputy Director of Research, NUS |
| 1998 - 1999 |
Chairman, Policy Research Program, NUS |
| 2000 |
Director of Institutional Resources & Special Duties, National University of Singapore |
| 2001 |
Director of Research, National University of Singapore |
| 2001 - 2003 |
Vice Provost (Budget & Planning), National University of Singapore |
| Oct 2004 - Mar 2008 |
Dean/Chair, School of Physical and Mathematical Sciences, NTU |
| Aug 2006 - |
Dean, College of Science, NTU |