Energy Efficiency: A Guide to Current and Emerging Technologies is the fourth and final major CAE project, carried out between 1993 and 1996. It was published in 1996 in two volumes – Volume 1, Buildings and Transportation, dealing with domestic, commercial and industrial buildings and transport, and Volume 2, Primary Production and Industry, dealing with primary production, food processing, forestry processing and manufacturing and minerals. Volume 2 also includes a section on general energy efficiency technologies. The focus of the two volumes is on energy efficiency technologies currently available and applied overseas, but not widely used in New Zealand, and on emerging technologies that are likely to prove practical for New Zealand within the next decade. While the emphasis is on New Zealand experience, the technologies discussed have application worldwide. Barriers that might restrict the use of individual technologies are also discussed.