| GEOGHEGAN, Nicole Ann ACTIVE | Secretary | 29 Nov 2024 | | | | Seventh Floor, 70 St Mary Axe, London, EC3A 8BE, United Kingdom |
| TAYLOR, Susannah Natalie ACTIVE | Director | 08 Jul 2024 | | United Kingdom | July 1975 | Seventh Floor, 70 St Mary Axe, London, EC3A 8BE, United Kingdom |
| WILLIS, Helen Margaret ACTIVE | Director | 31 Mar 2024 | | United Kingdom | January 1964 | Seventh Floor, 70 St Mary Axe, London, EC3A 8BE, United Kingdom |
| FRANKS, Clive Leonard RESIGNED | Secretary | 30 Apr 1998 | 31 May 2011 | | | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB, United Kingdom |
| RACE, Brian William RESIGNED | Secretary | | 30 Apr 1998 | | | 53 Clarendon Way, Chislehurst, Kent, BR7 6RG |
| SINGLETERRY, Maria RESIGNED | Secretary | 01 Sep 2020 | 29 Nov 2024 | | | Seventh Floor, 70 St Mary Axe, London, EC3A 8BE, United Kingdom |
| WOOD, Tracey Alison RESIGNED | Secretary | 01 Jun 2011 | 01 Sep 2020 | | | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB, United Kingdom |
| ARMITT, John Alexander RESIGNED | Director | 09 Apr 1997 | 30 Jun 2001 | | February 1946 | The Manor House, The Lee, Great Missenden, Buckinghamshire, HP16 9NA |
| BICKERSTAFF, Anthony Oliver RESIGNED | Director | 05 Jun 2006 | 30 Nov 2020 | England | June 1964 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| BROWNE, Nicholas Woodliffe RESIGNED | Director | 01 Jul 1993 | 31 Oct 1994 | | April 1941 | Broomhill Calthorpe Road, Fleet, Hampshire, GU51 4LN |
| CAMPBELL, John Richmond RESIGNED | Director | 19 Aug 1993 | 02 Jun 2000 | | July 1944 | 2 Sutton Avenue, Slough, Berkshire, SL3 7AW |
| CHARLES, Colin Scott RESIGNED | Director | | 31 Oct 1994 | | February 1939 | Pinewood 51 Oldfield Drive, Heswall, Wirral, Merseyside, L60 6SS |
| CLEMENTS, Warren John RESIGNED | Director | 18 Mar 2022 | 31 Mar 2024 | United Kingdom | August 1972 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| DOUGHTY, Stuart John RESIGNED | Director | 01 Jul 2001 | 12 Sep 2005 | United Kingdom | September 1943 | Bradley Farm House, Kinlet, Bewdley, Worcestershire, DY12 3BU |
| DUBE, William Ernest RESIGNED | Director | 08 Apr 2002 | 13 Oct 2003 | | September 1963 | 2 Carlton Lake Drive, Newark, Nottinghamshire, NG23 6NL |
| DUCKETT, Melvyn RESIGNED | Director | 01 Jan 1995 | 31 Mar 1998 | | May 1941 | 13 Princes Drive, Marple, Stockport, Cheshire, SK6 6NJ |
| GERRETSEN, Wolbert RESIGNED | Director | | 25 Jun 1992 | | February 1942 | Stones Throw Pennypot Lane, Chobham, Woking, Surrey, GU24 8DL |
| HALFORD, Leslie RESIGNED | Director | 01 Jan 1995 | 30 Apr 2002 | United Kingdom | June 1950 | 1 Dorset Avenue, Bramhall, Stockport, Cheshire, SK7 3NU |
| HUNTER, Martin David RESIGNED | Director | 01 Sep 2020 | 18 Mar 2022 | England | March 1959 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| LEE, Stephen Warwick RESIGNED | Director | 01 Nov 1994 | 12 Feb 1999 | | April 1950 | 6 Chapel Garth, Northallerton, North Yorkshire, DL7 0QF |
| LIGGETT, Nigel Lovatt RESIGNED | Director | 01 Jan 1995 | 30 Nov 2001 | | March 1949 | 17 Meadow Drive, Prestbury, Macclesfield, Cheshire, SK10 4EY |
| LOVELL, Alan Charles RESIGNED | Director | 26 Sep 1995 | 08 Apr 1997 | England | November 1953 | The Palace House, Bishops Lane, Bishops Waltham, Hampshire, SO32 1DP |
| MCCOLE, Charles Joseph RESIGNED | Director | 26 Apr 2002 | 04 Jun 2006 | England | September 1952 | Chimneys, 9 Woodcote Place, Ascot, Berkshire, SL5 7JT |
| NOBLE, Timothy John RESIGNED | Director | | 30 Sep 1993 | | January 1946 | Smallgrove, Rotherfield, Sussex, TN6 3HH |
| PINKNEY, Francis Stewart RESIGNED | Director | | 31 Dec 1998 | | September 1942 | 318 Manchester Road, Timperley, Altrincham, Cheshire, WA14 5NB |
| REEVES, Jenner Walker RESIGNED | Director | | 31 Jan 1995 | | July 1932 | Eiffel, 35 Brimstage Road Heswall Hills, Wirral, Merseyside, L60 1XE |
| ROBERTS, Miles William RESIGNED | Director | 02 Jun 2000 | 31 Dec 2001 | | February 1964 | 2 Grafton Place, Standon, Hertfordshire, SG11 1LT |
| ROBERTSON, Malcolm Charles Webster RESIGNED | Director | 01 Jan 1995 | 03 Jan 1997 | | July 1950 | New Grange Farm Rudyard Road, Rudyard, Leek, Staffordshire, ST13 8PF |
| STEINER, Leon RESIGNED | Director | 01 Nov 1994 | 31 Oct 1996 | | May 1944 | 8 Wallenger Avenue, Gidea Park, Romford, Essex, RM2 6ER |
| SWEENEY, Charles Alan RESIGNED | Director | 01 Dec 2003 | 30 Nov 2012 | England | May 1959 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| TAYLOR, David Roy RESIGNED | Director | 30 Nov 2020 | 08 Jul 2024 | United Kingdom | August 1964 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| WOOD, Tracey Alison RESIGNED | Director | 07 May 2019 | 01 Sep 2020 | England | May 1969 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |
| WYLLIE, Andrew RESIGNED | Director | 12 Sep 2005 | 07 May 2019 | England | December 1962 | Costain House, Vanwall Business Park, Maidenhead, Berkshire, SL6 4UB |