Micellar chromatography comprises chromatographic modes in which surfactant micelles, present above the critical micelle concentration, constitute a mobile or pseudostationary phase that participates directly in solute retention. In micellar liquid chromatography, solutes distribute among bulk mobile phase, micelles, and a packed stationary phase; association with micelles and adsorption of surfactant on the packing modify both elution strength and selectivity ^[1]. In micellar electrokinetic chromatography, charged micelles migrate electrophoretically at a velocity different from the electroosmotic flow, creating a moving pseudostationary phase into which neutral and ionic solutes partition ^[2]. The defining equilibrium is reversible solute–micelle association, characterized by micellar composition and concentration. The concept excludes conventional reversed-phase chromatography without micelles, ion-pair chromatography below the critical micelle concentration, and separations using unrelated vesicles or nanoparticles. Essential features are a surfactant concentration above its critical micelle concentration, stable micelles under the separation conditions, and retention or migration that depends measurably on micellar partitioning.