An electroluminescent (EL) material is one which emits EM radiation in the visible or near visible range when an electric field is applied to it. EL materials have a vast array of applications in the illumination and displays industries, from cheap and energy efficient lighting to large high resolution flat panel displays. This edited volume begins with a chapter outlining the basic physical principles of electroluminescence. The chapters that follow review in detail the preparation methods, physico-chemical structures, characterisation and applications of all classes of EL materials, ranging from the traditional materials already in common usage through to the more exotic materials such as GaN and organics. A final chapter will compare and contrast these different materials in various application contexts.