Finding new inorganic scintillator crystals with better performance for demanding applications, such as high-energy physics, medical imaging, and radiation detection, has been a long-standing challenge. Thanks to an intensive interdisciplinary effort between theoreticians, experimentalists and crystal growers, current scintillator performances are reaching the intrinsic limits imposed by the crystal. However, demand continues for more efficient scintillators with higher light output, better energy resolution and lower cost of production. This article discusses the basic concepts of scintillation in inorganic materials, focusing on how physics can provide pathways to assist in scintillator discovery. Published by Elsevier B.V.