Baker Hughes Inteq

Baker Petrolite

Baroid Drilling Fluids Division of Halliburton

BioLab Water Additives

BJ Services AS

BP Chemicals Ltd.

Castrol Offshore

CECA SA

Champion Technologies

Clariant Oil Services

Cognis Germany GmbH

Dow

Dow Corning Ltd

Drilling Specialties Co

Elementis Specialities

FIS Chemicals

Halliburton Energy Services

Huntsman Surface Sciences UK Ltd

Kelco Oilfield Group

Lamberti Spa

Lubrizol GB Ltd.

Meade-King, Robinson & Co Ltd.

MeadWestvaco

MI Drilling Fluids

Nalco Ltd. - Energy Services Division

Petrochem Carless Ltd

Rhodia Consumer Specialties Ltd

Roemex Ltd.

Rohm & Haas (UK) Ltd

Schlumberger

SIP Ltd.

SKW Polymers GmbH

Solutia Services International SA/NV

Tetra Technologies (UK) Ltd

Uniqema

=New Member (2005)