| Name | Country | Region | |
| The Paul Elliott Consultancy (CI) Ltd | British Channel Islands | Guernsey | St. Saviour |
| The Due Diligence and Investigation Company Ltd | British Channel Islands | Jersey | St Helier |
| Radar Detectives | Italy | Italy | Livorno |
| Radar Detectives | Italy | Italy | Livorno |
| Corporate Research and Investigations | Qatar | Doha | PO Box 27774 |
| Walker Love | UK | Aberdeenshire | Aberdeen |
| IP Forensics (GB) | UK | Avon | Bristol |
| Walker Love | UK | Ayrshire | Kilmarnock |
| Paul Read Investigations Ltd | UK | BERKSHIRE | READING |
| Standby Investigation | UK | Buckinghamshire | High Wycombe |
| Artemis Investigations Ltd | UK | Cambridgeshire | Cambridge |
| Blayze Ltd | UK | Cambridgeshire | Peterborough |
| Crown Associates International | UK | Cheshire | Dukinfield |
| Susan Ward Investigations | UK | Derbyshire | Morley |
| Richard Arthur Lee | UK | Essex | Chelmsford |
| Corporate Research and Investigations | UK | Greater London | London |
| FCRM Ltd | UK | Greater London | London |
| Eccora Ltd | UK | Greater London | London |
| Central Investigation Bureau Limited | UK | Hamsphire | Portsmouth |
| P&D Investigations Limited | UK | Hertfordshire | Welwyn Garden City |
| WM Investigation Ltd | UK | Hertfordshire | Hemel Hempstead |
| Walker Love | UK | Invernessshire | Inverness |
| Designed Professional Management Facilities Ltd | UK | Kent | Gravesend |
| Bunting and Baker | UK | Lincolnshire | Boston |
| Research Associates (Paul Hawkes) | UK | London | Marylebone |
| Walker Love | UK | Midlothian | Edinburgh |
| Grant & McMurtrie | UK | Midlothian | Edinburgh |
| Mr Andrew | UK | Midlothian | Edinburgh |
| Pegasus Investigations Ltd | UK | Midlothian | Edinburgh |
| Undique Global Consultancy | UK | Northamptonshire | Kettering |
| James Harris Investigations Limited | UK | Oxfordshire | Didcot |
| Brand Solutions International Limited | UK | Oxfordshire | Nr Bicester |
| Enquire International Limited | UK | Perthshire | Killin |
| Walker Love | UK | Renfrewshire | Paisley |
| Independant Investigation Co | UK | Somerset | Somerton |
| JBB Investigations | UK | South Yorkshire | Rotherham |
| Psci Merit | UK | Staffordshire | Wolverhampton |
| CMS Investigations | UK | Staffordshire | Burton on Trent |
| Grant & McMurtrie | UK | Strathclyde | Glasgow |
| Walker Love | UK | Strathclyde | Glasgow |
| Hogan and Co. International | UK | Surrey | Farnham |
| De Facto International | UK | Surrey | Twickenham |
| Blayze Ltd | UK | Swansea | Swansea |
| Security Risk Management Ltd | UK | Tyne and Wear | Newcastle Upon Tyne |
| Blayze Ltd | UK | West Glamorgan | Swansea |
| M C McNeill and Co | UK | West Lothian | Bathgate |
| Blayze Ltd | UK | Wiltshire | Swindon |