| LIMA SOLLERO, Alberto ACTIVE | Director | 11 Nov 2025 | | England | September 1981 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| ROOSENSCHOON, Emile ACTIVE | Director | 01 Oct 2025 | | England | February 1984 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| SIDDIQI, Saad Naved ACTIVE | Director | 11 Nov 2025 | | England | September 1978 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| GOULDING, Graham Thomas RESIGNED | Secretary | 05 Jun 1998 | 25 Apr 2003 | | | 126 Auckland Road, London, SE19 2RP |
| SWAYNE, Anthony William John RESIGNED | Secretary | | 30 Sep 1998 | | | The Old Vicarage, East Meon, Petersfield, Hampshire, GU32 1PG |
| WHISTLER, Christopher Claude Lashmer RESIGNED | Secretary | 04 Jun 2003 | 31 Dec 2020 | | | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| BUTLER, Geoffrey Doy Hopson RESIGNED | Director | 05 Jun 1998 | 31 Dec 2010 | England | October 1946 | Home Green Heath House Road, Worplesdon Hill, Woking, Surrey, GU22 0QU |
| CHURCH, Ian Berkeley RESIGNED | Director | | 30 Sep 1994 | | January 1927 | The Coach House, Whilton, Daventry, Northamptonshire, NN11 5NN |
| COOPER, Stephen Richard RESIGNED | Director | 12 Jun 2014 | 01 Oct 2025 | England | December 1966 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| CUBITT, Michael Harry RESIGNED | Director | 05 Jun 1998 | 31 Dec 2010 | United Kingdom | July 1948 | 22 Landen Grove, Wokingham, Berkshire, RG41 1LL |
| DERRY, Raymond Frederick RESIGNED | Director | 29 Feb 1996 | 06 Mar 1996 | | August 1951 | Appleton, Oxenholme Lane, Natland, Kendal, Cumbria, LA9 7QH |
| FEAVIOUR, Roger St Denis RESIGNED | Director | | 05 Jun 1998 | England | November 1946 | Hazeley House, High Street Chieveley, Newbury, Berkshire, RG20 8UX |
| FOX, Richard Murray RESIGNED | Director | | 13 Jan 1995 | | June 1932 | The Old Rectory, Itchenor, Chichester, West Sussex, PO20 7AB |
| GEDDES, Euan Michael Ross, The Lord RESIGNED | Director | | 31 Mar 1993 | United Kingdom | September 1937 | 25 Hugh Street, London, SW1V 1QJ |
| GOULDING, Graham Thomas RESIGNED | Director | 05 Jun 1998 | 25 Apr 2003 | England | June 1949 | 126 Auckland Road, London, SE19 2RP |
| JANSEN, Johannes Gregorius Alphons Marie RESIGNED | Director | 10 Dec 2010 | 12 Jun 2014 | Usa | March 1962 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| JORDAN, Robert RESIGNED | Director | 07 Oct 1993 | 07 Apr 1998 | United Kingdom | July 1936 | Ledgewood, Ryland Road Barford, Warwick, Warwickshire, CV35 8BY |
| KAYE, James Maxwell RESIGNED | Director | 01 Aug 1995 | 07 Apr 1998 | | August 1937 | Hill Cottage 3 Cock-A-Dobby, Sandhurst, Camberley, Surrey, GU17 8LB |
| LECLERCQ, Herve Michal RESIGNED | Director | 03 Oct 2011 | 12 Jun 2014 | United Kingdom | June 1962 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| NAVARRA, Stephane RESIGNED | Director | 10 Dec 2010 | 30 Sep 2011 | France | August 1965 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| PREST, Richard Jullion RESIGNED | Director | | 05 Jun 1998 | | May 1946 | Gardens House, Thoresby Park, Newark, Nottinghamshire, NG22 9EH |
| REITEMEIER, Christophe Nicolas RESIGNED | Director | 06 Nov 2020 | 02 Dec 2025 | England | December 1965 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| STUBBS, Graham Martin RESIGNED | Director | 10 Dec 2010 | 01 Jul 2014 | United Kingdom | February 1954 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| SWAYNE, Anthony William John RESIGNED | Director | | 30 Sep 1998 | United Kingdom | September 1948 | The Old Vicarage, East Meon, Petersfield, Hampshire, GU32 1PG |
| WHISTLER, Christopher Claude Lashmer RESIGNED | Director | 04 Jun 2003 | 31 Dec 2020 | England | June 1958 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| WOODWORTH, Ronald Leslie RESIGNED | Director | | 31 May 1993 | England | September 1941 | 3c Hallgarth, Newby Wiske, Northallerton, North Yorkshire, DL7 9JL |
| ZAMAN, Shaima RESIGNED | Director | 05 Dec 2024 | 11 Nov 2025 | England | December 1976 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |