With the advent of the comparatively new disciplines of remote sensing and non-destructive evaluation of materials, the topic of inverse scattering has broadened from its origins in elementary particle physics to encompass a diversity of applications. One such area which is of increasing importance in inverse scattering within the context of electromagnetism and this text aims to serve as an introduction to that particular speciality. The subject's development has progressed at the hands of engineers, mathematicians and physicists alike, with an inevitable disparity of emphasis and notation. One of the main objectives of this text is to distill the essence of the subject and to present it in the form of a graduated and coherent development of ideas and techniques. The text provides a physical approach to inverse scattering solutions, emphasizing the applied aspects rather than the mathematical rigour. The authors' teaching and research backgrounds in physics, electrical engineering and applied mathematics enable them to explore and stress the cross disciplinary nature of the subject. This treatment will be of use to anyone embarking on a theoretical or practical study of inverse electromagnetic scattering.