| Alan Tony Eckford | Director | 9 Nov 2001 | 8 Jan 2002 | British | 78 years |
| Alan Tony Eckford | Director | 8 Jan 2002 | 1 Sept 2003 | British | 78 years |
| Andrew Lindsay Scott | Director | 29 Sept 2008 | 29 Apr 2016 | British | 57 years |
| Andrew Simon Nield | Director | 25 Feb 1994 | 15 Nov 1995 | British | 70 years |
| Anthony Donnelly | Director | 20 Mar 2013 | 22 Nov 2023 | British | 62 years |
| Catherine Mary Moulton | Director | 30 Nov 2007 | 10 Nov 2010 | American | 66 years |
| Catherine Mary Moulton | Director | 26 Jul 2012 | 31 Mar 2015 | American | 66 years |
| Charles Baird Morrison | Director | 23 Oct 2003 | 30 Nov 2007 | British | 75 years |
| David Charles Turner | Secretary | 19 Aug 2002 | 24 Feb 2006 | Other | - |
| David Martin Oliver | Director | 3 Oct 1995 | 14 Jan 1997 | British | 70 years |
| Elizabeth Ann Horlock Clarke | Secretary | 1 Apr 2015 | 29 Mar 2021 | - | - |
| Geoffrey Arthur George Shepheard | Secretary | 23 Aug 2004 | 31 Mar 2015 | British | - |
| Jacqueline Elizabeth Fox | Secretary | 4 May 1992 | 17 May 2002 | British | - |
| James Barrie Peddie | Director | 4 May 1992 | 19 Feb 1993 | British | 89 years |
| Jonathan David Forster | Director | 1 Jun 2012 | 1 Jun 2012 | British | 59 years |
| Kevin Anthony Bromboszcz | Director | 14 Jan 1997 | 4 Jun 2001 | British | 72 years |
| Lee Shipsey | Director | 29 Apr 2016 | 26 Oct 2016 | British | 58 years |
| Malcolm William George Gibb | Director | 4 May 1992 | 1 Aug 1995 | British | 86 years |
| Mark Driver | Director | 1 Oct 2016 | 25 May 2018 | British | 59 years |
| Mark Stephen Anderson | Director | 10 Nov 2010 | 31 May 2012 | British | 61 years |
| Michael David Everest | Director | 3 Oct 1995 | 14 Jan 1997 | British | 66 years |
| Michael William Harrison | Director | 1 Sept 2003 | 30 Nov 2007 | British | 71 years |
| Neil George Manning | Director | 15 Dec 2008 | 20 Mar 2013 | British | 57 years |
| Neil Johnston | Director | 4 Jun 2001 | 28 Apr 2006 | British | 72 years |
| Peter Howarth | Director | 4 May 1992 | 31 Jan 1994 | British | 85 years |
| Richard Alistair Boucher | Director | 11 Feb 2020 | 1 Mar 2024 | British | 57 years |
| Robert Edwin Wilson | Director | 1 Apr 2015 | 26 Oct 2016 | British | 69 years |
| Roy Alan Pointer | Director | 21 Oct 1992 | 14 Jan 1997 | British | 81 years |
| Seamus Joseph Gillen | Secretary | 17 May 2002 | 19 Aug 2002 | British | - |
| Susannah Mary Clements | Director | 30 Nov 2007 | 30 Sept 2008 | British | 63 years |
| Timothy John Pettifor | Director | 14 Jan 1997 | 9 Nov 2001 | British | 73 years |
| Tom Bower | Director | 29 Sept 2008 | 30 Apr 2014 | British | 77 years |
| Wayne Paul Young | Director | 1 Apr 2015 | 11 Feb 2020 | British | 50 years |