Generally, domains in ferroic materials are a special kind of twin defect that occurs to counter the effect of the stray fields generated during phase transformation from a highly symmetric phase to a low symmetric phase. Domain walls serve as a boundary between two or more domains, either antiparallel (forming 180° domain wall) or perpendicular (forming 90° domain wall), based on the direction of the order parameter. The science and engineering of domain and domain wall motions are highly significant as this plays a crucial role in hysteresis modification and property enhancement in ferroic materials. This chapter shall attempt to capture some of the fundamental concepts of domain and domain wall formation and the types/kinds of domain walls discussed based on the nature of the change of the polar order at the domain wall plane. Domain wall motions, factors that restrict this motion, and the contribution of domain wall motion to switching polarization vectors will also be addressed. Various domain engineering techniques in ferroelectric single crystals, ceramics, polymers, and composites, as well as moods of applications such as memory storage, capacitors, and sensors, shall be explored in this chapter.