This book treats state-of-the-art computer methods for power flow studies and contingency analysis. The authors present the relevant computer methods and mathematical concepts and power flow and contingency analysis are treated. Furthermore, traditional methods to solve such problems are compared to modern solvers, developed using the knowledge of the first part of the book. Finally, these solvers are analyzed both theoretically and experimentally, clearly showing the benefits of the modern approach. It can serve as a text for advanced power system courses to inform prospective power engineers of methods currently employed in the electric utility industry. Because of the increasing use of the computer as an indispensable tool in power system engineering, this book will also serve as a basic reference for power system engineers responsible for the development of computer applications.