Liquid organic salts are a new class of polar, selective phases for gas chromatography. The presence of coulombic forces within the melt are available to enhance polar interactions. Solute-phase interactions are characterized by weak dispersive interactions, strong orientation interactions, and a wide range of proton acceptor capabilities. The properties of these new phases are reviewed with an emphasis on the liquid range of the salts, the efficiency of column packings and open-tubular columns prepared with liquid organic salts, the strength of selective interactions and the bearing of the ion type on these interactions, and the potential for chemical reactions of solutes with the melt. Because the liquid organic salts have a clearly defined chemical structure, reproducible via synthesis, and welldefined physical and chemical properties, they are suitable for use as standard reference polar phases for gas chromatography.