One way of defining the scope of a volume such as this is to develop a consistent view of the audience. We have three primary categories of readers in mind, and have attempted to make the organization and presentation of the material, and the level of mathematics in the exposition, consistent with their presumed needs. The first group of readers that we seek to reach are those who are responsible for energy planning activities in the developing countries themselves. The typical head of a national energy planning institution and his senior staff, often has an academic background in engineering, and work experience in an electric utility or an oil company. It is they who are responsible for the analytical focus of the planning activity, and it is they who interact with foreign counterparts in technical assistance projects. What they frequently lack in discussions with foreign consultants, and in evaluating technical approaches for modeling and analysis, is an objective yardstick based on experience in other countries. Much of the case material, and guidance we provide on the selection and content of models, is directed at this audience. This may not be a very large audience, numerically, but it is nevertheless a very important one.

Secondly, we hope that the book might serve as a text in courses at the graduate, as well as post-graduate, level. The authors have served a faculty in a wide variety of courses sponsored by Universities in several countries, and by both multilateral and bilateral assistance agencies, that, over the last 15 years, have helped train many thousands of officials from some 70 countries.