Shinohara and co-authors present a comprehensive and in-depth discussion of all current wireless power transfer (WPT) methods and meet the growing need for a detailed understanding of the advantages, disadvantages, and applications of each method. WPT is a game-changing technology, not only for IoT networks and sensors, but also for mobile chargers, long-flying drones, solar-powered satellites, and more, and the list of potential applications will continue to grow. Each author’s chapter is based on a minimum of 13 years and a maximum of over 30 years of research experience on selected WPT technologies to explain the theory and advantages and disadvantages of this to various applications. The book provides an insight into WPT theories and technologies, including inductive coupling for short-distance WPT, radio waves for long-distance WPT, optical WPT using lasers, supersonic WPT in water, and more. The characteristics of each WPT method are compared theoretically and technically. The differences of each WPT method are explained with reference to the different theories, techniques, and suitable applications. The reader will gain an understanding of the recent and future commercial market and regulations regarding WPT. They will be able to apply this knowledge to select the appropriate WPT method for their desired application. This book is appropriate for students, WPT researchers, and engineers in industry who are developing WPT applications.