Electrochemistry provides a very interesting and versatile means for the selective reduction or oxidation of organic compounds. By addition (reduction) or removal (oxidation) of electrons, organic substrates are activated. Thus, starting from neutral compounds, radical anions (reduction) or radical cations (oxidation) are formed (Scheme 22.1). Therefore, organic electrochemistry may be considered as the chemistry of radical ions. As compared with redox reagents, the selectivity of the electrochemical redox process can be determined by the selection of the electrode potential (see below). Furthermore, as the electrons are not bound to a reagent, no waste from used-up reagents is produced. The ecologically and economically problematic waste treatment can be avoided to a large extent.