The principle of the electron photoejection technique is explained. This approach leads to the formation of transient spectra of unstable intermediates, allowing their recording and providing their extinction coefficients. Moreover, it permits determination of their electron affinities and the rates of their reactions, whether spontaneous or with some added substrates. Application of this technique to studies of disproportionation of radical anions has been most profitable. It led to the determination of the forward and backward rate constants of disproportionation of a variety of radical anions, and to discovery and quantification of some subtle features of these reactions. The electron photoejection technique provided the data characterizing the electron transfer initiation of anionic polymerization and clarified some of its features. Other opportunities provided by the electron photoejection in studies of electron transfer processes are suggested.