■ American Gas Association
■ American Institute of Mining, Metallurgical, and Petroleum Engineers
■ American Petroleum Institute
■ American Society of Petroleum Operations Engineers
■ Australian Institute of Energy
■ Brunel Institute of Power Systems 
■ Canadian Society of Petroleum Geologists
■ Euroheat & Power 
■ Gas Processors Association
■ Institute of Energy 
■ Institute of High Energy Physics 
■ International Energy Agency
■ Moscow Power Engineering Institute
■ National Oil Recyclers Association
■ National Petroleum Council
■ Petroleum Exploration Society
■ Society of Petroleum Engineers