This is the first book-length, integrated treatment of impedance spectroscopy with an emphasis on solid state electrochemical systems. Impedance spectroscopy is a method for characterizing the electrical behavior of systems in which the overall system behavior is determined by a number of coupled processes, each proceeding at a different rate. The scope of this volume is comprehensive: providing coverage of fundamental theory, illustrating applications of the technique, and discussing practical considerations in regard to data acquisition and analysis. Those with little prior experience in impedance measurements will find this an excellent introduction. Senior investigators will find that the book provides a useful summary of fundamentals as well as a survey of recent developments in the field.