Aculab Plc (UK)

AGC-Tel Consultants Ltd. (UK)

Allied Telesyn KK (formerly Teltrend, New Zealand)
Amp Holland B.V (Netherlands)
Ascom Tateco AB (Switzerland) 
Aspect Telecommunications Ltd (UK)
Advanced Technology RAMAR Ltd (UK)
Avaya Communications (EMEA)

BABT Product Service Limited (UK)

Bang and Olufsen Telecom A/S (Denmark)

Bosch Telecom Danmark A/S (Denmark)
British Telecommunications plc (UK)
Brooktrout Technology Inc (USA) 
Canon (Japan)

Communication Certification Laboratory (CCL, USA) Compaq Computer EMEA BV (Germany)
Concert Communications (USA)

CS Telecom (France)
CSELT (Italy) 
Curtis-Straus LLC (USA)

De La Rue Card Systems (UK)

DSC Communications Corporation (USA) 
ECI-Telecom (formerly Telematics International, USA) 
ECI-Telecom (Israel)

ELSA GmbH (Germany)

EuroPacketCable Forum (Europe)

European Commission (EU)

European Telecommunications Standards Institute (EU) Fritelco GmbH (Germany)
Heikimian Laboratories, Inc. (USA)

IBM Corp (USA)
Intel Denmark ApS (Denmark)

Institute of Telecommunications (IL, Poland)

Kingston Telecom' Laboratories Ltd. (KTL Worldwide, UK) Liberty Global Operations (NL)
LONIIS (Russian Federation)
Loughborough Sound Images (UK) 
Lucent Technologies Inc (USA)

Lucent Technologies Wireless (EMEA)

Melita International (USA) 

Microsoft Corporation (USA)
Ministry of Economy (CTÚ, Czech Republic)

Ministry of Transport (Dept of Communications, Latvia)

Ministry of Transport (Turkey) 
Mitel Semiconductor Limited (UK) 
Mitel Telecom Limited (UK) 
Mitsubishi Electric Europe (France)

Motorola Inc. (Semiconductor Product Sector, USA) Motorola Inc. (Personal Communications)
Motorola Inc. (Internet & Networking Group, USA) Motorola Limited (UK)
Network Equipment Technologies (Europe) Ltd (NET, UK)

Newbridge Networks Corporation (Canada)
Newbridge Networks Limited (UK)
Nokia Mobile Phones (Germany)
Nortel Networks (USA)

Nuera Communications, Inc. (USA)
Paradyne Corporation (USA)
Polycom, Inc. (USA)

Polyspan Teleconferencing B.V. (NL) 
R&TTE Compliance Association (Europe) 
Radio Frequency Investigation Ltd (RFI, UK) 
Ricoh Company Limited (Japan)

Shiva Europe Limited (UK)

Singapore Productivity & Standards Board

SOMA Networks, Inc. (USA)

Sourcecom Corporation (UK)
Taylor Woodrow plc (UK) 
TDK Systems Inc. (USA)

Telcordia Technologies (formerly - ICC, UK)

Teltrend (formerly Securicor 3NET, New Zealand and UK)

TÚ SR (Slovak Republic)

TUV Product Service (UK)

Underwriters Laboratories, Inc. (UL, USA) 
Unitymedia GmbH (DE)
VINA Technologies Ltd (UK)
Wearnes Peripherals International (Pte) Ltd (Singapore)