This silicon α-effect was first observed in the late 1960s by researchers at Bayer AG as an increase in reactivity at the silicon atom for hydrolysis and was used for cross-linking of α-silane-terminated prepolymers. For a long time after that, people attributed this reactivity as silicon α-effect. However, the real mechanism beneath it had been debated for many years after this discovery. Generally, this effect has been rationalized as an intramolecular donor-acceptor interaction between the lone pair of the organofunctional group (such as NR, OC(O)R, N(H)COOMe) and the silicon atom. However, this hypothesis has been proved incorrect by Mitzel and coworkers and more experiments are needed to interpret this effect.