Instead of relying on the usual price elasticity technique, this book combines economic and engineering analysis to study economic growth and energy demands to the year 2000. It asserts that future energy demand will be determined by two basic factors--the gross national product (GNP) and the efficiency with which energy is used to produce this output in the household, commercial, industrial, and transport sectors of the economy. Labor hours multiplied by a productivity factor results in the GNP. This study predicts that, in the long run, productivity in the United States will recover most of the sharp losses registered in the past five years. The study points out the decelerating population growth, the higher number of women in the labor force, and new investments as having an influence on this situation. After projecting the size and composition of each of the four energy consuming sectors that account for the total GNP. Energy and Economic Growth estimates efficiency improvements for each. It shows, for example, that higher levels of thermal insulation will reduce sharply energy needs for household heating and cooling. Similarly, the study notes that improvements in energy consumption per dollar of output can be made for each of the energy intensive manufacturing industries, nothing that although the savings in energy are significant, none is a consequence of pushing improvements to known technological limits. Finally, the book establishes the price elasticities that are inherent in the calculated energy requirements and checks these against elasticity estimates made by other researchers.