The gas chromatographic stationary phase properties of fifteen tetra- n-butyl-ammonium salts containing chloride, bromide,iodide, nitrate, nitrite, thiocyanate, perchlorate, hexafluorophosphate, tetrabutylborate, tetraphenylborate, picrate, tetrafluoroborate, 4-toluenesulfonate, methanesulfonate, and trifluoromethanesulfonate anions are described. For five of these salts the liquid temperature range exceed 100°C:4-toluenesulfonate (55-200°C), tetrafluoroborate (162-290°C), trifluoromethanesulfonate (112-240°C), picrate (90-200°C), and methanesulfonate (79-180°C). The tetra- n-butylammonium salts exhibit unique solute selectivity, manifested in very weak dispersion and proton donor interactions, accompanied by strong orientation and proton acceptor interactions. For the anions picrate, tetrabutylborate, trifluoromethanesulfonate, 4-toluenesulfonate, nitrate, methanesulfonate, bromide, nitrite, and chloride dipole interactions are fairly constant and change little with the anion type (except for chloride), while the proton acceptor capability of the salts is a strong function of the anion type, increasing in the following order: picrate ≈ trifluoromethanesulfonate < 4-toluenesulfonate < nitrate ≈ methanesulfonate < bromide < nitrite < chloride. The retention of organic solutes on tetra- n-butylammonium 4-toluenesulfonate, trifluoromethanesulfonate, methanesulfonate, picrate, and chloride salts occurs primarily by gas-liquid partition. Gas-liquid adsorption makes a small but significant contribution to the retention of hydrocarbons and to a lesser extent that of pyridine, but in general, does not contribute to the retention of polar solutes. The chromatographic characteristics of the tetra- n-butylammonium salts are illustrated by the separation of some essential oils.