This book by Prof Yang is an excellent book for people want to know more about piezoelectricity and piezoelectric devices.It starts with a complete theory of piezoelectricity with the intention to get readers familirize with the fundamentals. This part is complicated from its appearance, but there is a purpose. Such formulation is essential in dealing with complicated issues which discussed in detail later, ie the effect of various bias fields like thermo, stress, acceleration and so on.After descriptions of the basic nonlinear theory, the chapters followed restore to the linear theory for various strctural elements and applications as devices. It touched almost all applications of acosutic devices with simple analytical solutions.The methods and techniques are not directly related to the engineering solutions of actual problems, but it is the first step you have to take towards the direction.I highly recommend this book to graduate students and engineers who are interested in advanced knowledge on this subject.