The following section presents some basic concepts of performance and briefly discusses the notion of productive (technical and allocative) efficiency. Third section discusses the criteria for performance evaluation in general and the criteria that would be used in this study in particular. Physical, financial and productivity indicators are discussed in section fourth, fifth and sixth respectively. Seventh section discusses the production function approach to calculate the trend in growth of total factor productivity. Methodology used to determine the economies of scale has discussed in section eight. Finally, the chapter has concluded in section nine by presenting the list of those physical, financial and productivity indicators which would be used in this study to evaluate the performance of electric power and telecommunications industry in Pakistan.