This updated introductory textbook covers the most important developments that are taking place in the electric power industry. Although the topic areas and depth of coverage remain about the same, this edition provides a more complete treatment of the power flow-based techniques in a new chapter which deals with optimal power flow. The discussion on unit commitment has been expanded to include the LaGrange relaxation approach. The chapter on interchange transactions provides students with an appreciation of the complications that may accompany a competitive market for the generation of electric energy. Sections on security analysis have been updated to incorporate the use of bounding and other contingency selection methods.