| Name | | | |
| Caribbean Investigative Network | Bermuda | Pembroke | 62 St Johns Rd |
| Richard Arthur Lee Consulting Ltd | Germany | Rheinisch-Bergischer Kreis | Wermelskirchen |
| Proficient Surveyors and Co | Hong Kong | Shaukeiwan | 324 Shaukeiwan Rload |
| Radar Detectives | Italy | Italy | Livorno |
| James Reid & Son | UK | Aberdeenshire | Aberdeen |
| Walker Love | UK | Argyll | Oban |
| Walker Love | UK | Ayrshire | Kilmarnock |
| Southern Law Services | UK | Berkshire | Reading |
| Standby Investigation | UK | Buckinghamshire | High Wycombe |
| D.Nightingale Vehicle Consultant | UK | Cambridgeshire | March |
| Counter Crime Limited | UK | Cambridgeshire | Huntingdon |
| Blayze Ltd | UK | Carmarthenshire | Ammanford |
| Walker Love | UK | Dunbartonshire | Dumbarton |
| Independant Investigation Co | UK | East Sussex | Crowborough |
| Aitch-Gee Investigation Ltd | UK | Essex | Brentwood |
| Richard Arthur Lee Consulting Ltd | UK | Essex | Chelmsford |
| Ms Pride | UK | Gloucestershire | Stroud |
| British American Investigations and Security Ltd | UK | Greater London | London |
| Eccora Ltd | UK | Greater London | London |
| Gwent Legal Services | UK | Gwent | Newport |
| Total Fleet Management | UK | Hampshire | Petersfield |
| Central Investigation Bureau Limited | UK | Hamsphire | Portsmouth |
| C.SIAPPS Associates | UK | Hertfordshire | Hertford |
| P&D Investigations Limited | UK | Hertfordshire | Welwyn Garden City |
| Cobra Investigation Consultants | UK | Kent | Birchington |
| Walker Love | UK | Lanarkshire | Hamilton |
| RTA Investigations | UK | Lancashire | Rochdale |
| Bunting and Baker | UK | Lincolnshire | Boston |
| Research Associates (Paul Hawkes) | UK | London | Notting Hill Gate |
| Walker Love | UK | Midlothian | Edinburgh |
| Grant & McMurtrie | UK | Midlothian | Edinburgh |
| Mr Andrew | UK | Midlothian | Edinburgh |
| Pegasus Investigations Ltd | UK | Midlothian | Edinburgh |
| Mr Beare | UK | Oxfordshire | Oxford |
| A D Duncan Investigations and Precognitions | UK | Shetland Islands | SCALLOWAY, Lerwick |
| JBB Investigations | UK | South Yorkshire | Rotherham |
| Fox Investigations Ltd | UK | Strathclyde | Glasgow |
| Grant & McMurtrie | UK | Strathclyde | Glasgow |
| Walker Love | UK | Strathclyde | Glasgow |
| Eurocom CI Limited | UK | Surrey | Leatherhead |
| Derby Associates Ltd | UK | Surrey | Ashtead |
| Blayze Ltd | UK | West Glamorgan | Swansea |
| M C McNeill and Co | UK | West Lothian | Bathgate |
| Batsford and Bellamy | UK | West Midlands | Birmingham |
| Blayze Ltd | UK | West Midlands | Birmingham |
| Blayze Ltd | UK | Wiltshire | Swindon |