Excess enthalpies and excess heat capacities of quaternary mixtures containing ethanol, N,N-dimethylformamide, tetrahydrofuran, and cyclohexane have been measured, at 25 degrees C, with a 'home-built' flow calorimeter already described. Semiempirical models like UNIQUAC and Wang-Benson were used to correlate experimental data. A number of empirical equations were also used to verify their ability to predict quaternary properties from binary information alone and also, when available, from ternary parameters. Some of these methods, usually devised only for predicting ternary properties, were modified to make them suitable for quaternary mixtures. They were also tested with other literature data.