3Di
USA, spatial data solutions and management tools for Geographic Information Systems

ABB Energy Interactive Inc.
USA, developer of retail energy information systems and services

Accenture
USA; management and technology consulting organization

ACDAT System Services Ltd.
Canada; database, networks and systems management to information system departments in the oil and gas industry

ACRT, Inc.
international professional service and training organization in the utility and urban forestry, arboricultural, environmental, natural resource, biological, and horticultural sciences

ADB Systems
Norway, software vendor focused on integrated eProcurement and Enterprise Asset Management software solutions

Advantica
UK; gas technology area formerly of British Gas

Advantica Technologies Ltd.
UK, technology and engineering solutions for gas networks

AEA Technology
UK, advanced technology, consultancy and technical services

Allegro Development
USA, software, e-commerce solutions

Alphatania
UK; training programs for gas professionals

Altra Energy Technologies L.L.C.
USA; energy management systems; electronic trading services; Streamline; Chalkboard; Gas Management System; Engenius, e-commerce

American Management Systems
USA, information technology consulting