Surface acoustic waves (SAWs) demonstrate simplicity of their excitation and receipt, as well as their availability to all propagation ways of signal branching and processing. SAW devices are divided into several main classes: filters for signal processing at intermediate frequencies, delay lines, resonators, filters with low losses for the input circuits of receiver, and antenna duplexers for the connected receivers. The SAW devices are not only able to conduct an effective signal processing, but also serve as a basis for multi-subsystems (matched filtering, signal processing, real-time Fourier transform processors, etc.). Additionally, SAW filters help scientists to realize the wide variety of frequency characteristics. Besides their unique electrical characteristics, SAW devices favorably differ from their analogs in small size, mechanical strength and high reliability, due to the quality of raw materials and their processing. The use of the photolithography and the achievements of group microelectronic technology in their production allow a researcher to achieve good reproducibility of parameters at relatively low cost. In addition, currently SAW devices are widely used in various sensors based on the SAW radio frequency identification. This book presents an attempt to generalize a multi-year experience on R&D of SAW devices. It develops original approaches directed at discovering solutions of technical problems, as development of various SAW devices are patented in Russia. Moreover, the book presents some experimental and theoretical research results.