High-performance ion-exchange separation of small inorganic and organic ions, usually with suppressed or non-suppressed conductivity detection, constitutes ion chromatography (IC) in analytical chemistry. A low-capacity ion-exchange column is eluted with a dilute aqueous eluent; after chemical or electrolytic suppression of the eluent’s background conductivity, the analyte ions are recorded as conductivity peaks, although UV, amperometric, or mass-spectrometric detection may be used instead ^[1]. Combustion ion chromatography converts organically bound fluorine or other heteroatoms to inorganic ions before the chromatographic step, which is still IC of those ions ^[2]. Conceptual boundaries exclude gas-phase ion mobility sometimes also called ion chromatography, and they exclude general ion-exchange chromatography of proteins that is not configured as high-performance IC of small ions. Essential features are an ion-exchange separator, an eluent whose strength is matched to monovalent and divalent ions, and a detection scheme that reports ionic equivalents. Silver-ion chromatography of lipids is a related but distinct complexation mode and is not IC in the suppressed-conductivity sense ^[3].