This book details both conventional and advanced geophysical techniques with description of the Electromagnetic (EM) based physics involved in different methodologies of magnetotellurics (MT). It offers detailed discussions of the theory of EM and MT methods, and the operation of specific instruments, including the presentation of results and their interpretation in tabular format. The chapters describe the conceptual background of MT geophysical methods along with the related instrumentation, sufficient illustrations, and the applicability of the individual methodologies supported by successful case histories. Features: Provides a comprehensive introduction to the MT-geophysical method. Covers diverse geotectonic settings with several case studies, supported by diagrams and data tables. Describes the fundamentals of uncontrollable telluric and controllable non-telluric sources used in MT surveys. Reviews MT methods with emphasis on recent improvements, recognizing both static and distortion effects and their treatment in the analysis of impedance tensors in 3-D inversion codes. Explores integrated MT interpretation coupled with seismic and potential (gravity, magnetic) geophysical methods. This book is aimed at professionals, students, and researchers in geophysics, geology, civil, mechanical, petroleum, and geothermal engineering, and other branches of earth and environmental sciences.