| Adam James Nicholas Robinson | Director | 17 Sept 1998 | 4 Mar 2003 | British | 67 years |
| Amanda Jane Willmott | Director | 1 Nov 2005 | 6 Jul 2016 | British | 71 years |
| Andrew William Robert James | Director | 12 Jun 1997 | 30 Aug 2005 | British | 63 years |
| Christopher Niall Bridgmore Brown | Director | 20 Jun 1991 | 30 Nov 1994 | British | 70 years |
| Christopher Niall Bridgmore Brown | Director | 1 Jan 2004 | 6 Jul 2016 | British | 70 years |
| David Anthony Hardie | Director | 12 Feb 2001 | 1 Oct 2009 | Scottish | 82 years |
| Edward John Willoughby Gardner | Director | 18 Sept 2001 | 6 Jul 2016 | British | 56 years |
| Edward Percy Keswick Weatherall | Director | 18 Mar 2009 | 6 Jul 2016 | British | 69 years |
| James Alexander Brown | Director | 20 Jun 1991 | 14 Jul 1999 | British | 80 years |
| James Alexander Brown | Secretary | 20 Jun 1991 | 14 Jul 1999 | British | - |
| James David Sherrington | Director | 6 Jul 2016 | 11 Jan 2021 | British | 50 years |
| James David Sherrington | Secretary | 6 Jul 2016 | 11 Jan 2021 | - | - |
| Katherine Anne Felgate | Director | 18 Jan 1996 | 18 May 2001 | British/austrailia | 61 years |
| Lucy Knowles | Director | 18 Sept 2001 | 30 Apr 2013 | British | 54 years |
| Malcolm Brian Johnston Kimmins | Director | 20 Jun 1991 | 12 Feb 2001 | British | 89 years |
| Paul Stanton Masters | Director | 1 Jul 1999 | 6 Jul 2016 | British | 75 years |
| Peter Mockford | Director | 28 Mar 1994 | 21 Mar 1996 | British | 70 years |
| Robert Gerard Finch | Director | 20 Jun 1991 | 23 Apr 2001 | British | 82 years |
| Robert William Greenham Evans | Director | 20 Jun 1991 | 31 Dec 2011 | British | 74 years |
| Sally Woodward | Director | 24 Jan 2000 | 5 Feb 2001 | British | 65 years |
| Sarah Heward | Director | 20 Jun 1991 | 9 Jan 2004 | British | 61 years |
| Sarah Reid | Director | 26 May 2004 | 31 Mar 2007 | British | 56 years |
| Simon Ward-nicholson | Director | 1 Oct 2008 | 12 Oct 2012 | British | 50 years |
| Tristram Charles Edward Hillier | Director | 1 Jan 2007 | 31 Aug 2011 | British | 51 years |
| Winston Spencer Brian Sanderson | Director | 16 Dec 1993 | 12 Sept 2000 | British | 63 years |
| Winston Spencer Brian Sanderson | Secretary | 14 Jul 1999 | 6 Jul 2016 | British | - |