| Alexander Grant | Director | 9 Mar 1999 | 30 Mar 2004 | British | 70 years |
| Andreas Brabeck Letmathe | Director | 9 Jan 2004 | 31 Aug 2012 | Austrian | 60 years |
| Andres Friedrich Leuberger | Director | 13 Jul 1991 | 9 Mar 1999 | Swiss | 87 years |
| Armin Maximilian Kessler | Director | 13 Jul 1991 | 16 Jun 1995 | American | 87 years |
| Arthur Nicholas Winston Soames | Director | 13 Jul 1991 | 15 Apr 1992 | British | 77 years |
| Basil Williamson | Director | 21 Feb 1997 | 9 Mar 1999 | British | 81 years |
| Beat Christoph Kraehenmann | Director | 5 Mar 2014 | 11 Jul 2022 | Swiss | 68 years |
| Benan Cuma | Director | 1 Nov 2020 | 31 Jul 2024 | Turkish | 51 years |
| Christiane Schumacher | Director | 10 Jun 2016 | 1 Mar 2017 | German | 49 years |
| Christopher Stuart Parker | Director | 7 Aug 2012 | 1 Jul 2017 | Australian | 67 years |
| David Griffiths | Director | 13 Jul 1991 | 16 Jul 1994 | British | 78 years |
| David James Jackson | Director | 16 Jul 1994 | 30 Sept 2001 | British | 78 years |
| David Peter Clough | Director | 13 Jul 1991 | 9 Mar 1999 | British | 79 years |
| Derek John Bailey | Secretary | 13 Jul 1991 | 30 Apr 1993 | British | - |
| Franz Bernhard Humer | Director | 16 Jun 1995 | 9 Mar 1999 | Swiss | 79 years |
| Gavin Keith Bell | Director | 10 Mar 1995 | 9 Mar 1999 | British | 81 years |
| James Karin Jnr Lennertz | Director | 14 Jan 2002 | 9 Jan 2004 | American | 72 years |
| James Lyndon Davies | Director | 13 Jul 1991 | 9 Mar 1999 | British | 80 years |
| Jan Van Den Boer | Director | 22 Jul 2004 | 7 Aug 2012 | Dutch | 79 years |
| Jayson Donald Alexander Dallas | Director | 1 Jan 2013 | 24 Jul 2015 | Usa | 57 years |
| John Anthony Goldsmith | Director | 13 Jul 1991 | 20 Sept 1991 | British | 88 years |
| John Mcmillan Melville | Director | 14 Jun 2000 | 31 Dec 2012 | British | 74 years |
| John Nevill Hornibrook | Director | 13 Jul 1991 | 30 Apr 1993 | British | 97 years |
| John Phillip Rackley | Director | 10 Mar 1995 | 9 Mar 1999 | British | 67 years |
| Kenneth John Stone | Director | 2 Oct 1992 | 14 Oct 1994 | British | 82 years |
| Kenneth Martin Taylor | Director | 13 Jul 1991 | 16 Dec 1994 | New Zealand | 82 years |
| Kezia Jayn Vitug | Director | 1 Mar 2019 | 31 Oct 2020 | American,filipino | 49 years |
| Mandy Elizabeth Robertson | Secretary | 9 Jul 2018 | 12 Mar 2019 | - | - |
| Mark Lloyd Williams | Director | 31 Aug 2012 | 30 May 2014 | Uk | 54 years |
| Nicol Adrian Holladay | Director | 14 Oct 1994 | 24 Oct 1997 | British | 77 years |
| Olufunke Abimbola | Secretary | 22 Jun 2015 | 6 Jul 2018 | - | - |
| Paul Anthony Newton-syms | Director | 13 Jul 1991 | 2 Oct 1992 | British | 81 years |
| Peter John Frederick Summerfield | Director | 13 Jul 1991 | 31 Dec 1991 | British | 75 years |
| Richard David Daniel | Secretary | 16 Jul 1994 | 22 Jun 2015 | British | - |
| Richard John Wright | Director | 24 Jul 2015 | 1 Sept 2015 | British | 52 years |
| Richard William Erwin | Director | 1 Sept 2015 | 3 Jul 2025 | British | 58 years |
| Thomas Mcdonald Mcclymont | Director | 27 Apr 1993 | 21 Feb 1997 | British | 81 years |
| Timothy Edwin Kelly | Director | 1 Mar 2017 | 31 Dec 2018 | American | 53 years |
| Tobin Charles Schilke | Director | 4 Aug 2014 | 10 Jun 2016 | American | 51 years |
| Vic Ackermann | Director | 24 Oct 1997 | 14 Jun 2000 | Australian | 81 years |