| 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 |
| DE TURRIS, Atillia Gabriella RESIGNED | Secretary | 18 Mar 1996 | 06 Feb 1998 | | | 8 Vineyard Mews, Preston Place, Richmond Upon Thames, Surrey, TW10 6DD |
| DONALD, Keith Malcolm Hamilton RESIGNED | Secretary | 17 Oct 1994 | 30 Nov 1995 | | | 251 Upper Richmond Road, London, SW15 6SW |
| FLINT, Matthew James RESIGNED | Secretary | 01 Aug 2012 | 01 Mar 2025 | | | Carlton House, Regent Park, 299 Kingston Road, Leatherhead, Surrey, KT22 7SG, England |
| GOULDING, Graham Thomas RESIGNED | Secretary | 12 Jun 1998 | 25 Apr 2003 | | | 126 Auckland Road, London, SE19 2RP |
| PRICHARD, Teresa Joan RESIGNED | Secretary | 06 Feb 1998 | 12 Jun 1998 | | | 4 Bracken Gardens, Barnes, London, SW13 9HW |
| RICE, Stephen Euston RESIGNED | Secretary | | 17 Oct 1994 | | | 9 Martindale Walk, Brierley Hill, West Midlands, DY5 2RX |
| WHISTLER, Christopher Claude Lashmer RESIGNED | Secretary | 04 Jun 2003 | 01 Aug 2012 | | | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| ZAMAN, Shaima RESIGNED | Secretary | 01 Mar 2025 | 11 Nov 2025 | | | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| BRICK, Leroy William RESIGNED | Director | | 13 Oct 1994 | | October 1927 | 802 Mandy Lane, Camp Hill, Pa 17001, FOREIGN, Usa |
| BUTLER, Geoffrey Doy Hopson RESIGNED | Director | 21 Jun 1995 | 31 Dec 2010 | England | October 1946 | Home Green Heath House Road, Worplesdon Hill, Woking, Surrey, GU22 0QU |
| CAMPANARO, Leonard Anthony RESIGNED | Director | 13 Oct 1994 | 31 Jul 2000 | | May 1948 | 1704 Olmstead Way East, Camp Hill, Pennsylvania, 17011845, Usa |
| 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 | 31 Jul 2000 | 31 Dec 2010 | United Kingdom | July 1948 | 22 Landen Grove, Wokingham, Berkshire, RG41 1LL |
| ETZWEILER, William David RESIGNED | Director | | 03 Feb 1998 | | December 1935 | 110 Pelham Drive, Camp Hill, Pennsylvania, 17011, Usa |
| FAZZOLARI, Salvatore Domenico RESIGNED | Director | 03 Feb 1998 | 23 Feb 2012 | United States | August 1952 | 1827 Red Spruce Lane, Mechanicsburg, Pennsylvania 17050, United States |
| HATHAWAY, Derek Charles RESIGNED | Director | | 18 Dec 2007 | | May 1944 | 7 Northwatch Lane, Mechanicsburg, Pennsylvania, PA17055, Usa |
| HATHAWAY, John Walter RESIGNED | Director | | 17 Oct 1994 | | June 1938 | Cherrydene Halfpenny Green, Bobbington, Stourbridge, West Midlands, DY7 5EN |
| JACOBY, Scott William RESIGNED | Director | 08 Mar 2010 | 01 Jul 2014 | Usa | May 1966 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| LECLERCQ, Herve Michal RESIGNED | Director | 03 Oct 2011 | 16 Dec 2013 | United Kingdom | June 1962 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| MACDONALD, Alexander James RESIGNED | Director | 10 Dec 2010 | 26 Nov 2013 | United Kingdom | December 1954 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| MCGALPINE, Christopher RESIGNED | Director | 10 Dec 2010 | 26 Nov 2013 | England | May 1962 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| NAVARRA, Stephane RESIGNED | Director | 10 Dec 2010 | 30 Sep 2011 | France | August 1966 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| NEUFFER, Richard Carl RESIGNED | Director | 29 Apr 2008 | 01 Mar 2010 | | March 1942 | 11 Cedar Waxwing Road, Hackettstown, New Jersey 07840, United States Of America |
| NEWMAN, Robert George RESIGNED | Director | | 29 Apr 2008 | | July 1949 | 105 Otter Trail, West Columbia, South Carolina, 29169, Usa |
| O'KELLY, Paul Brian RESIGNED | Director | 10 Dec 2010 | 05 Dec 2011 | United Kingdom | December 1957 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| REITEMEIER, Christophe Nicolas RESIGNED | Director | 31 Dec 2020 | 02 Dec 2025 | England | December 1965 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |
| STUBBS, Graham Martin RESIGNED | Director | 05 Dec 2011 | 01 Jul 2014 | United Kingdom | February 1954 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| TAPPAN JNR, Moore RESIGNED | Director | | 13 Oct 1994 | | January 1929 | 805 E Sylvan Drive, Brandon, Florida, FOREIGN, Usa |
| WHISTLER, Christopher Claude Lashmer RESIGNED | Director | 08 Mar 2010 | 31 Dec 2020 | England | June 1958 | Harsco House, Regent Park, 299 Kingston Road Leatherhead, Surrey, KT22 7SG |
| ZAMAN, Shaima RESIGNED | Director | 05 Dec 2024 | 11 Nov 2025 | England | December 1976 | Office 3a Capital Tower, 91 Waterloo Road, London, SE1 8RT, England |