This textbook introduces electrical engineering students to the most relevant concepts and techniques in three major areas today in power system engineering, namely analysis, security and deregulation. The book carefully integrates theory and practical applications. It emphasizes power flow analysis, details analysis problems in systems with fault conditions, and discusses transient stability problems as well. In addition, students can acquire software development skills in MATLAB and in the usage of state-of-the-art software tools such as Power World Simulator (PWS) and Siemens’ PSS/E. The book is interspersed with problems for a sound understanding of various aspects of power systems. The questions at the end of each chapter are provided to reinforce the knowledge of students as well as prepare them from the examination point of view. The book will be useful to both the undergraduate students of electrical engineering and postgraduate students of power engineering and power management in several courses such as Power System Analysis, Electricity Deregulation, Power System Security, Restructured Power Systems, as well as laboratory courses in Power System Simulation.