This book presents the basic physical properties, structure, fabrication methods and applications of ferroelectric materials. These are widely used in various devices, such as piezoelectric/electrostrictive transducers and actuators, pyroelectric infrared detectors, optical integrated circuits, optical data storage, display devices, etc. The ferroelectric materials described in this book include a relatively complete list of practical and promising ferroelectric single crystals, bulk ceramics and thin films. Included are perovskite-type, lithium niobate, tungsten-bronze-type, water-soluable crystals and other inorganic materials, as well as organic ferroelectrics (polymers, liquid crystals, and composites). Basic concepts, principles and methods for the physical property characteristics of ferroelectric materials are introduced in the first two chapters for those readers new to the subject of ferroelectricity. Not only professional researchers and engineers but also students and other readers who have limited physical knowledge and an interest in ferroelectrics, will welcome this book.