Multiple-photon-accumulating strategies such as consecutive photoelectron transfer (conPET) and triplet-triplet annihilation upconversion (TTA-UC), have represented an elegant means to achieve powerful SET reductions, but their use in oxidations has so far been elusive. However, these techniques place limiting requirements on reactions, such as the requirement in conPET for both ground and radical ion states to be visible-light active. Furthermore, net-oxidative/reductive PRC processes employ excess of a sacrificial oxidant/reductant which is necessary for photocatalyst turnover, but which may (or whose by-products may) i) interfere with the desired downstream chemistry and ii) may require separation from the desired products. The conPET strategy likewise suffers from this requirement. In comparison to PRC processes, SOE can employ uncapped potentials to chemical redox reactions at the turn of a dial. However, electrode surfaces typically cannot discriminate between organic molecules aside from their innate order of thermodynamic redox potentials. Moreover, low electrical conductivity in organic solvents typically require applied potentials to be higher than the redox potential of the target substrate. This encourages deleterious higher order or solvent redox processes especially if target SET processes lie near the solvent electroactive window (+3 to -3 V for typical electrolyte-containing solvents). In addition, mechanistic characterization of the heterogeneous "electrocatalysis" step (referring to heterogeneous SET at the electrode surface) has remained a key challenge in SOE. Screening of electrode materials is often inevitable, despite best efforts to characterize materials by overpotential, electrical resistivity, surface area, stability and cost. As a result of these limitations, in recent years synthetic photoelectochemistry is emerging as a state-of-the-art in SET-mediated chemistry. Different categories for the merger of photochemistry and electrochemistry have been reported, including interfacial photoelectrochemistry (iPEC) involving photoelectrodes and decoupled photoelectrochemistry (dPEC) where photo-and electrochemical steps serve separate roles in the reaction mechanism. A third category involves an intimate and synergistic relationship of photo-and electrochemical steps within the same catalytic cycle. (40-51) A variety of nomenclature has been coined in the literature for this sub-category of PEC, such as: "electrophotocatalysis" (45-47,51) "photoelectrocatalysis" and "electron-primed photoredox catalysis" . We coined the general nomenclature "electrochemically-mediated PhotoRedox Catalysis (e-PRC)" as a blanket term to cover both net-oxidative and net-reductive variants and to avoid misunderstanding with iPEC. e-PRC leverages the unique benefits of both parent technologies PRC and SOE in order to i) compile potential and photon energies to achieve photocatalyst excited-state potentials beyond those normally accessible via visible light photons alone and to ii) obviate the need for sacrificial oxidants/reductants. Pioneering reports on e-PRC realized these benefits in a number of net-reductive/net-oxidative transformations. parameters of e-PRCats; an important concept which has not yet been disclosed. Although moderate oxidants in their tris(para-substituted)biarylaminium (TPA .+ ) state, subsequent photooxidation would provide formidable oxidation potentials. Moreover, the excellent stability of isolated TPA .+ s could be leveraged in i) probing the reaction mechanisms of their e-PRC reactions and ii) their photophysical characterization. Herein, we disclose TPAs as powerful and effective e-PRCats that engage unactivated or electron-poor aromatic systems (E p ox = +2.1 V to >3.0 V) in SET oxidation. Of key importance is the discovery of precomplexation in the ground state, which i) circumvents ultrashort lifetimes of excited states, ii) allows engagement of higher order excited states and iii) enables contra-thermodynamic redox selectivity. Photoexcited triarylaminium radical cations are demonstrated as novel superoxidants in organic synthesis (Figure ).