There are good reasons why the subject of electric power engineering, after many years of neglect, is making a comeback in the undergraduate curriculum of many electrical engineering departments. The most obvious is the current public awareness of the "energy crisis. " More fundamental is the concern with social responsibility among college students in general and engineering students in particular. After all, electric power remains one of the cornerstones of our civilization, and the well-publicized problems of ecology, economy, safety, dependability and natural resources management pose ever-growing challenges to the best minds in the engineering community. Before an engineer can successfully involve himself in such problems, he must first be familiar with the main components of electric power systems. This text­ book will assist him in acquiring the necessary familiarity. The course for which this book is mainly intended can be taken by any student who has had some cir­ cuit analysis (using discrete elements, and including sinusoidal steady state) and elementary electromagnetic field theory. Most students taking the course will be in their junior or senior years. Once the course is completed, students may decide to go more deeply into the design and operation of these components and study them on a more advanced level, or they may direct their attention to the problems of the system itself, problems which are only hinted at briefly at various points herein.