Electromagnetic (EM) wave scattering is of fundamental importance to antenna and radar design engineering, and the increasing interest in metamaterials has created a need for new approaches to solving scattering problems for characterizing engineered media. This book lays the theoretical foundation for new computer programs in computational electromagnetics (CEM) and meets the need of today's researchers. This book represents over 30 years of the author's experience teaching this topic, with extensive lectures notes expanded to include advanced concepts and mathematical solutions to cover modern effects on metamaterials and related advanced complexities. Problems and solutions at the end of each chapter help to reinforce concepts and highlight applications. This is an ideal text for advanced graduate students and researchers in EM and applied physics.