| Adam Charles Little | Director | 23 Apr 2003 | 3 Aug 2007 | British | 75 years |
| Alastair Macleod Graham | Director | 6 Dec 2004 | 31 Mar 2009 | British | 73 years |
| Andrea Margaret Thomas | Secretary | 1 Sept 1997 | 1 Feb 2009 | Other | - |
| Anne Louise Shaw | Director | 31 Mar 2009 | 31 Jul 2010 | United States | 64 years |
| Ariel David Flores | Director | 8 Jun 2020 | 25 Mar 2022 | American | 49 years |
| Brian Peevor | Secretary | 1 Apr 1994 | 31 Aug 1997 | British | - |
| Christopher Kuangcheng Gerald Eng | Secretary | 23 Mar 2009 | 30 Jun 2010 | - | - |
| David Alan Rider | Director | 6 Oct 2014 | 30 Nov 2020 | British | 62 years |
| David Brian Skidmore | Director | 1 Jun 2008 | 31 Mar 2009 | United States | 69 years |
| Douglas Patrick Chapman | Director | 1 Apr 1994 | 1 Feb 2003 | British | 76 years |
| Francis William Michael Starkie | Director | 1 Jul 2007 | 30 Sept 2009 | British | 77 years |
| George Islay Macneill Robertson | Director | 16 Dec 2014 | 1 May 2020 | British | 80 years |
| James Grant Nemeth | Director | 1 Feb 2003 | 3 Aug 2005 | Us Citizen | 69 years |
| James Stephen Blythe | Director | 10 Oct 2011 | 1 Dec 2014 | British | 71 years |
| Jan Clayton Lyons | Director | 28 Aug 2020 | 6 Apr 2021 | American | 61 years |
| Jeremy Huck | Director | 31 Mar 2009 | 1 May 2012 | British / Us Citizen | 59 years |
| Joanne Elizabeth Cross | Director | 12 Dec 2014 | 8 Mar 2022 | British | 61 years |
| John Gordon Sinclair Buchanan | Director | 1 Oct 1996 | 21 Nov 2002 | British | 83 years |
| Joseph Richard Murphy | Director | 17 Apr 2022 | 5 Sept 2025 | British | 54 years |
| Karen Maclennan | Director | 30 Nov 2020 | 25 Mar 2022 | British | 55 years |
| Katherine Anne Thomson | Director | 1 Dec 2014 | 1 Jan 2016 | British | 58 years |
| Kenneth James Mowbray Walder | Director | 5 Dec 1992 | 1 Jan 1993 | British | 84 years |
| Michael Edmund Townshend | Director | 1 Jun 2013 | 15 Dec 2014 | British | 68 years |
| Nicholas John Charles Evans | Director | 6 Apr 2021 | 25 Mar 2022 | British | 57 years |
| Peter Barrie Pugh Bevan | Director | 1 Jan 1993 | 30 Dec 1998 | British | 82 years |
| Peter Norman Hobbs | Director | 5 Dec 1992 | 31 Mar 1994 | British | 83 years |
| Richard Charles Grayson | Secretary | 5 Dec 1992 | 31 Mar 1994 | British | - |
| Richard Mark Syms | Director | 8 Jun 2020 | 25 Mar 2022 | British | 60 years |
| Richard Scott Sloan | Director | 1 May 2012 | 1 Jun 2013 | Us Uk Citzen | 62 years |
| Richard Turquand Jungius | Director | 6 Dec 2004 | 1 Jun 2008 | British | 73 years |
| Robert Carl Fearnley | Director | 3 Aug 2007 | 10 Oct 2011 | British | 63 years |
| Robert Norris | Director | 22 Sept 2010 | 15 Dec 2014 | American | 72 years |
| Rodney Frank Chase | Director | 5 Dec 1992 | 23 Apr 2003 | British | 83 years |
| Roger Christopher Harrington | Director | 1 Oct 2009 | 6 Oct 2014 | British | 60 years |
| Sandra Jean Macrae | Director | 1 Jan 2016 | 28 Aug 2020 | British | 63 years |
| Stephen James Ahearne | Director | 5 Dec 1992 | 30 Sept 1996 | British | 87 years |
| Yasmin Stanley Ali | Secretary | 1 Feb 2009 | 30 Jun 2010 | Other | - |