| COOP, Richard Paul ACTIVE | Secretary | 26 Apr 2024 | | | | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| GEIER-CIBIN, Ralf Manfred ACTIVE | Director | 16 Jul 2018 | | Switzerland | August 1962 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| SCHWALLER, Johann Claude ACTIVE | Director | 01 May 2024 | | United Kingdom | February 1993 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| WRANKMORE, Martin ACTIVE | Director | 01 Nov 2023 | | United Kingdom | March 1976 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| ANTHONY WILKINSON, Katherine Frances RESIGNED | Secretary | 28 Jun 1996 | 13 Feb 2001 | | | Cranbrook 65 Long Ashton Road, Long Ashton, Bristol, Avon, BS41 9HW |
| DWYER, Daniel John RESIGNED | Nominee Secretary | 25 Aug 1992 | 25 Aug 1992 | | | 6 Brimstone Close, Chelsfield Park, Chelsfield, Kent, BR6 7ST |
| KENNEDY, Gerard RESIGNED | Secretary | 31 Jul 2003 | 26 Apr 2024 | | | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| SLATER, John Andrew Duncan RESIGNED | Secretary | 25 Aug 1992 | 28 Jun 1996 | | | 216 Bath Road, Slough, Berkshire, SL1 4EN |
| SYMES, Judith Ann RESIGNED | Secretary | 28 Jun 1996 | 31 Jul 2003 | | | 15 Prebend Mansions, Chiswick High Road, London, W4 2LU |
| ALLEN, Peter Vance RESIGNED | Director | 25 Aug 1992 | 31 Dec 1999 | | March 1956 | The Grove, Sonning, Berkshire |
| BAKER, Stephen Martin RESIGNED | Director | 02 Apr 2015 | 28 Apr 2017 | England | April 1955 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| BATES, Gordon Edward RESIGNED | Director | 21 Oct 2011 | 02 Apr 2015 | United Kingdom | November 1965 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| BROWN, Michael Edward RESIGNED | Director | 02 Apr 2015 | 21 May 2020 | United Kingdom | July 1959 | 228, Bath Road, Slough, SL1 4DX, England |
| CARTER, Nick RESIGNED | Director | 25 Apr 2017 | 01 Jul 2021 | England | August 1981 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| CHAKRAWERTTI, Sandeepan RESIGNED | Director | 01 Jul 2021 | 01 May 2024 | United Kingdom | March 1986 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| DOYLE, Betty June RESIGNED | Nominee Director | 25 Aug 1992 | 25 Aug 1992 | | June 1936 | 8 The Bartons, Elstree Hill North, Elstree, Herts, WD6 3EN |
| DWYER, Daniel John RESIGNED | Nominee Director | 25 Aug 1992 | 25 Aug 1992 | | April 1941 | 6 Brimstone Close, Chelsfield Park, Chelsfield, Kent, BR6 7ST |
| FELLNER, Peter John, Dr RESIGNED | Director | 25 Aug 1992 | 02 Dec 1997 | | December 1943 | 216 Bath Road, Slough, Berkshire, SL1 4EN |
| GARFIELD, Edward RESIGNED | Director | 25 Apr 2017 | 08 Nov 2024 | England | June 1978 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| GEIER CIBIN, Ralf RESIGNED | Director | 20 Dec 2001 | 30 Apr 2009 | | August 1962 | 27 Gardiner Close, Abingdon, Oxfordshire, OX14 3YA |
| GEMUEND, Markus RESIGNED | Director | 20 Dec 2001 | 31 May 2004 | | May 1958 | 47 Appleton Street, Boston, Ma, 02116, Usa |
| HAAG, Toralf, Dr RESIGNED | Director | 30 Aug 2005 | 15 Mar 2016 | Germany | March 1966 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| HERGET, Alexander RESIGNED | Director | 21 May 2020 | 31 Oct 2023 | England | December 1965 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| IMWINKELRIED, Rene, Dr RESIGNED | Director | 20 Jun 2003 | 27 Aug 2004 | | August 1957 | Landstrasse 64, Naters, Vs 3904, Switzerland |
| KLEMENT, Gerhard Franz RESIGNED | Director | 10 Aug 2004 | 01 Aug 2005 | | November 1952 | 14 Hunter Drive, Hampton, New Hampshire Nh 03842, FOREIGN, Usa |
| KUTZER, Stephan, Dr RESIGNED | Director | 01 Aug 2005 | 01 Jul 2014 | Usa | November 1965 | 89 Tidewater Farm Road, Greenland, New Hampshire, FOREIGN, Usa |
| MANUEL, Johan Pieter RESIGNED | Director | 28 Jun 1996 | 30 Sep 1997 | | January 1943 | 23 Rue J H Petri, Mulhouse, F68100, Switzerland |
| MARKETZ, Herbert, Doctor RESIGNED | Director | 28 Jun 1996 | 12 Nov 1999 | | March 1941 | Finkenstrasse 25, Obervil, CH 4104, Switzerland |
| NICHOLLS, Peter Geoffrey RESIGNED | Director | 03 Oct 1994 | 28 Jun 1996 | England | June 1949 | 216 Bath Road, Slough, Berkshire, SL1 4EN |
| OPRANDI, Peter RESIGNED | Director | 30 Apr 2009 | 02 Apr 2015 | Usa | June 1968 | 228 Bath Road, Slough, Berkshire, SL1 4DX |
| ROBINSON, Edward Raymond RESIGNED | Director | 10 Oct 1997 | 01 Sep 2000 | | July 1952 | 25 Monks Road, Virginia Water, Surrey, GU25 4RR |
| ROSS, Iain Gladstone RESIGNED | Director | 25 Aug 1992 | 31 Oct 1995 | England | January 1954 | Herons Ghyll, Tilford Road, Tilford, Surrey, GU10 2DD |
| RUPP, Richard Helmut RESIGNED | Director | 05 Apr 2000 | 09 May 2002 | | June 1947 | Baselblick 1, 79540 Loerrach, Germany |
| SAVITZKY, Rodolfo RESIGNED | Director | 02 Apr 2015 | 16 Jul 2018 | Switzerland | March 1962 | 38, Muenchensteinerstrasse, Basel, Switzerland |
| SHOTT, Ian Dermot RESIGNED | Director | 28 Jun 1996 | 08 Jul 1998 | | February 1957 | 9 Rue Charles Riescher, St Louis 68300, France |
| STURGE, Simon John RESIGNED | Director | 01 Nov 1995 | 10 Oct 1997 | | March 1959 | 216 Bath Road, Slough, Berkshire, SL1 4EN |
| WAIBEL, Roland Michael, Dr RESIGNED | Director | 05 Apr 2000 | 30 Aug 2005 | Switzerland | April 1958 | Hasenrain 36, Therwil, 4106, Switzerland |