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Organocatalysis is the acceleration of a chemical transformation by a small organic molecule that is not a metal complex and is regenerated during the catalytic cycle ^[1][2]. In advanced synthetic organic chemistry the concept is bounded by the exclusive use of organic compounds—typically amines, phosphoric acids, N-heterocyclic carbenes, or phosphines—as the catalytic species, thereby excluding transition-metal catalysis and biocatalysis as the primary mode of activation ^[2][3]. Essential features are a defined activation mode (enamine, iminium, Brønsted-acid, nucleophilic, or carbene umpolung), turnover of the organic catalyst, and, in asymmetric organocatalysis, a chiral catalyst that differentiates prochiral faces of the substrate ^[2]. N-Heterocyclic carbenes operate by forming covalent Breslow-type intermediates that invert the polarity of carbonyl carbon atoms ^[1]. Phosphine organocatalysts add to electron-deficient π-systems to generate zwitterionic intermediates that mediate a range of annulations and substitutions ^[4]. Dual manifolds that merge a photoredox cycle with an organocatalytic cycle remain organocatalytic with respect to the bond-forming activation of the organic substrate ^[2]. The concept is distinguished from ligand-assisted metal catalysis, in which the organic molecule is not itself the catalytic center.