| Andrew Christopher Bolter | Director | 13 Jan 2014 | 4 Apr 2014 | British | 56 years |
| Clive Jonathan Mottram | Director | 15 Jun 2009 | 2 Jun 2010 | British | 67 years |
| Deborah Grimason | Director | 13 Apr 2007 | 19 Jun 2009 | British | 63 years |
| Deborah Grimason | Director | 1 Jan 2012 | 20 Nov 2013 | British | 63 years |
| Fiona Puleston Penhallurick | Director | 4 Apr 2014 | 15 Mar 2016 | British | 59 years |
| Gordon James Stanley | Director | 13 Apr 1992 | 31 Mar 1993 | British | 84 years |
| Guy Franklin Young | Director | 13 Jan 2014 | 31 Oct 2015 | South African | 57 years |
| Ian Maclean Reid | Director | 22 Nov 1994 | 4 Apr 2003 | British | 81 years |
| Jonathan Charles Bennett Houlton | Director | 1 Oct 1996 | 31 May 1998 | British | 65 years |
| Kevin Allan Abbott | Director | 30 Jun 1994 | 6 Oct 1994 | British | 72 years |
| Marie-cecile Collignon | Director | 1 Sept 2011 | 31 Dec 2011 | French | 50 years |
| Michael John Choules | Director | 12 Sept 2014 | 9 Apr 2021 | British | 66 years |
| Patrick John Scannell | Director | 22 Nov 1994 | 1 Oct 1996 | British | 75 years |
| Paul Francis William Cottrell | Director | 21 Nov 2022 | 26 Jul 2024 | British | 60 years |
| Peter William Joseph Mills | Director | 6 Apr 2003 | 30 Jun 2010 | British | 73 years |
| Philip John Margrave | Director | 31 Mar 1993 | 30 Jun 1994 | British | 76 years |
| Phillip Thomas Edward Lanyon | Director | 16 Aug 2010 | 13 Jan 2014 | British | 62 years |
| Raymond Alfred Elliott | Director | 31 May 1998 | 13 Apr 2007 | British | 79 years |
| Rebecca Joan Powell | Director | 5 Jan 2011 | 1 Sept 2011 | British | 54 years |
| Ronald Shuttleworth | Director | 13 Apr 1992 | 31 Jul 1995 | British | 81 years |
| Sonia Fennell | Director | 7 Jun 2010 | 5 Jan 2011 | British | 67 years |