| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Airplan Aviation Technical Services Ltd. | 02920102 | 26/06/1998 | Dissolved |
| Davy British Rail International Ltd | 01758773 | 31/12/2001 | Dissolved |
| Vineyard House Ltd | 01586245 | 31/12/2001 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| BURDEROP INVESTMENTS LIMITED | 02485284 | 01/05/1996 | 30/11/2011 | Dissolved |
| CONSTRUCTION INDUSTRY RESEARCH AND INFORMATION ASSOCIATION | 00790505 | 08/02/2007 | 28/05/2012 | Amber |
| CROUCH HOGG WATERMAN LIMITED | SC136186 | 19/06/1997 | 30/11/2011 | Dissolved |
| HALCROW (CONSULTING ENGINEERS & ARCHITECTS) LIMITED | 01045458 | 01/09/1997 | 30/11/2011 | Amber |
| HALCROW (USA) | 05285576 | 12/11/2004 | 02/12/2004 | Dissolved |
| HALCROW ASIA LIMITED | 02458827 | 10/01/2002 | 14/11/2011 | Bronze |
| HALCROW CANADA LIMITED | 05296410 | 25/11/2004 | 30/11/2011 | Dissolved |
| HALCROW CONSULTING LIMITED | 02326761 | 01/05/1995 | 30/11/2011 | Amber |
| HALCROW GILBERT ASSOCIATES LIMITED | 02312495 | 01/07/1994 | 30/11/2011 | Dissolved |
| HALCROW GROUP LIMITED | 03415971 | 06/08/1997 | 30/11/2011 | Amber |
| HALCROW HOLDINGS LIMITED | 01674044 | 01/02/1993 | 10/11/2011 | Bronze |
| HALCROW INTERNATIONAL LIMITED | 02326765 | 01/05/1996 | 30/11/2011 | Amber |
| HALCROW INTERNATIONAL PARTNERSHIP | 02809680 | 01/03/2006 | 30/11/2011 | Amber |
| HALCROW LIMITED | 02999602 | 08/12/1994 | 30/11/2011 | Dissolved |
| HALCROW STAFF AND SERVICES | 01193727 | 15/11/1992 | 30/11/2011 | Dissolved |
| HALCROW WATER SERVICES LIMITED | 03055857 | 19/06/2007 | 30/11/2011 | Dissolved |
| LEWIS R. CARNAN LIMITED | 01315274 | 16/03/2001 | 30/11/2011 | Dissolved |
| MECHANICAL AND ELECTRICAL DESIGN ASSOCIATES LIMITED | 00878811 | 24/12/1996 | 30/11/2011 | Dissolved |
| SIR WILLIAM HALCROW & PARTNERS (MALAYSIA) LIMITED | 02314593 | 01/09/1997 | 30/11/2011 | Dissolved |
| SIR WILLIAM HALCROW & PARTNERS LIMITED | 01722541 | 15/11/1991 | 30/11/2011 | Strike Off |
| TRANSECON INTERNATIONAL LIMITED | 02092471 | 21/01/2002 | 30/11/2011 | Dissolved |
| TRANSMARK (CONSULTANTS) LIMITED | 01048112 | 09/01/2002 | 30/11/2011 | Dissolved |
| TRANSMARK ASIA LIMITED | 02815214 | 24/05/1999 | 14/11/2011 | Bronze |
| TRANSMODE LIMITED | 01118784 | 09/01/2002 | 30/11/2011 | Dissolved |
| TRANSPORTATION SYSTEMS AND MARKET RESEARCH LIMITED | 00964333 | 31/12/2001 | 30/11/2011 | Dissolved |