| Allen Morrow Acheson | Director | 26 Apr 1991 | 13 Apr 1992 | American | 100 years |
| Angela Hoffman | Director | 7 Dec 2005 | 23 Jun 2006 | American | 61 years |
| Anthony Edward Collins | Director | 21 Dec 2007 | 16 Dec 2010 | British | 70 years |
| Bruce Alan Ainsworth | Director | 7 Dec 2005 | 21 Jun 2013 | American | 75 years |
| Charles Albert Gurney | Director | 12 Aug 1999 | 4 Sept 2000 | British | 59 years |
| Christine Anne Daly | Secretary | 21 Dec 2007 | 23 Jul 2014 | British | - |
| Christopher James Smith | Director | 6 Oct 2000 | 2 Dec 2005 | British | 71 years |
| Christopher William Timpson Scott | Director | 4 Dec 2020 | 4 Nov 2022 | British | 64 years |
| Clifford A Johnson Iii | Director | 12 Jan 2006 | 21 Dec 2007 | American | 81 years |
| Daniel Keith Mazany | Director | 16 Jun 1993 | 1 Sept 1999 | American | 80 years |
| Douglas Gene Smith | Director | 30 Nov 1999 | 30 Jan 2004 | Us | 77 years |
| Emma Kathryn Wrighton | Director | 21 Dec 2007 | 31 Dec 2011 | British | 53 years |
| Francis Declan Finbar Tempany Mccormack | Secretary | 23 Jul 2014 | 2 May 2022 | British | - |
| Frank Cockrell | Secretary | 26 Apr 1991 | 16 Jun 1993 | British | - |
| Fred Edward Schoenlaub | Director | 16 Jun 1993 | 9 Jan 1995 | Us Citizen | 96 years |
| Fred Edward Schoenlaub | Secretary | 16 Jun 1993 | 9 Jan 1995 | Us Citizen | - |
| George Christian Hedemann | Director | 9 Jan 1995 | 2 Jun 2008 | American | 83 years |
| George Christian Hedemann | Secretary | 9 Jan 1995 | 2 Jun 2008 | American | - |
| Ian Blacker | Director | 31 Aug 2022 | 14 Mar 2024 | British | 59 years |
| Ian Michael Robinson | Director | 21 Jun 2013 | 15 Jan 2021 | British | 61 years |
| Ian William Morham Moir | Director | 14 Apr 1992 | 20 Sept 1993 | British | 91 years |
| James Douglas Doull | Director | 15 Jan 2021 | 24 Jul 2025 | American | 65 years |
| James Learoy Patton | Director | 16 Jun 1993 | 24 Aug 2002 | Us Citizen | 85 years |
| James Stephen Hetherington | Director | 13 Aug 1997 | 30 Apr 1998 | British | 87 years |
| John Hamilton Robinson | Director | 1 Jun 1993 | 31 Mar 2000 | American | 76 years |
| John Youings | Director | 30 Nov 1999 | 21 Apr 2004 | British | 83 years |
| Lawrence Gareth Spencer Hughes | Director | 30 Nov 1999 | 8 Aug 2000 | British | 73 years |
| Matthew William Fairfax | Director | 4 Dec 2020 | 15 Jan 2021 | British | 57 years |
| Michael Charles Tresise | Director | 10 Dec 1996 | 8 Oct 2000 | British | 65 years |
| Patrick George Davidson | Director | 10 Dec 1996 | 6 Aug 2001 | American | 78 years |
| Paul Harmer | Director | 4 Dec 2020 | 31 Jul 2022 | British | 57 years |
| Paul James Adam | Director | 7 Jul 1989 | 30 Nov 1999 | American | 92 years |
| Robbie John Reed Gibson | Director | 4 Dec 2020 | 16 May 2025 | British | 43 years |
| Robert Glenwood Ruisch Jnr | Director | 16 Jun 1993 | 15 Jul 1996 | American | 87 years |
| Rolf Stamm | Director | 26 Apr 1991 | 16 Jun 1993 | American | 90 years |
| Rosemary Elizabeth Thomas | Director | 23 Apr 2004 | 30 Sept 2004 | British | 63 years |
| Thomas Reorda | Director | 8 Dec 2011 | 17 Jan 2014 | American | 71 years |
| Timothy Triplett | Director | 2 Jun 2008 | 17 Jan 2014 | American | 72 years |
| Timothy Triplett | Secretary | 2 Jun 2008 | 17 Jan 2014 | American | - |
| Wayne Frank Hall | Director | 16 Jun 1993 | 16 Feb 2006 | American | 82 years |
| Youssef Merjaneh | Director | 14 Apr 2021 | 29 Aug 2025 | German | 49 years |