Mechanisms of the defect creation in alkali halides induced by electronic excitation, suggested within these three decades, are surveyed, emphasizing how they are related to the overall yield of defect creation in solids. The experimental and theoretical studies which are critical check points for proposed mechanisms are discussed in detail. It is pointed out that the processes of localization of the wave functions of the electrons and holes and the conversion of localized electronic energy to the motion of the lattice atoms should be understood. The mechanisms of the dynamic motion of atoms to which the electronic energy is imparted and of the stabilization of the primary products, the neutral interstitials and vacancies in the halogen sublattice, are also discussed.