| Akshaya Bhargava | Director | 29 Jun 2015 | 11 Mar 2016 | British | 69 years |
| Christopher James Mack | Director | 5 Jun 2020 | 1 May 2023 | British | 54 years |
| David Jonathan Semaya | Director | 29 Sept 2010 | 9 Dec 2013 | American | 63 years |
| David Martin Dalton-brown | Director | 17 May 2010 | 31 Mar 2013 | British | 66 years |
| David Martin Dalton-brown | Director | 7 Jun 2013 | 31 Jul 2015 | British | 66 years |
| David Simpson | Director | 14 Aug 2009 | 22 Jun 2010 | British | 56 years |
| James Edward Fane De Salis | Director | 21 Jun 2013 | 31 Jan 2016 | British | 58 years |
| Jean-marc Morel | Director | 3 Sept 2018 | 1 Feb 2022 | French,south African | 51 years |
| Karl Arne Ingemar Hassel | Director | 16 Jun 2016 | 11 Jan 2019 | Swedish | 68 years |
| Mark Newbery | Director | 20 May 2016 | 8 Dec 2019 | British | 45 years |
| Mark Newbery | Director | 1 May 2023 | 1 May 2024 | British | 45 years |
| Martyn John Gatehouse | Director | 14 Aug 2009 | 20 Apr 2012 | British | 64 years |
| Michael Robert Fullalove | Director | 4 Nov 2015 | 31 Oct 2019 | British | 51 years |
| Nicholas Saul Arnold | Director | 14 Nov 2014 | 30 Mar 2016 | British | 48 years |
| Nicola Jane Eggers | Director | 29 Jun 2020 | 13 Mar 2024 | British | 54 years |
| Paul Albert Ford | Director | 14 Aug 2009 | 13 Apr 2010 | British | 56 years |
| Peter John Horrell | Director | 2 Sept 2010 | 2 May 2013 | British | 57 years |
| Philip William Best | Director | 9 Sept 2015 | 16 Jan 2018 | British | 65 years |
| Robert James Brown | Director | 1 Oct 2010 | 9 Feb 2012 | British | 60 years |
| Rory Thomas Tobin | Director | 1 Apr 2013 | 26 Sept 2014 | Irish,british | 60 years |
| Solomon Woldenhaimanot Soquar | Director | 16 Jul 2015 | 20 Feb 2020 | British,eritrean | 60 years |
| Terence William Dunleavy | Director | 14 Aug 2009 | 31 Aug 2016 | New Zealand | 61 years |
| Thomas Andre Rene Fekete | Director | 14 Aug 2009 | 22 Jun 2010 | French | 57 years |
| Thomas Rostron | Director | 2 Sept 2010 | 28 Sept 2012 | British | 65 years |
