The Martin-Hou equation of state is applied to liquid-liquid equilibrium. Excellent results are obtained for binary systems by using two binary Interaction parameters

which are temperature-dependent over a wide temperature range

but can be taken as constant over the narrow temperature range of 30 to 40 degrees. The prediction of VLE for binary systems at low pressures based on LLE data of binary systems are demonstrated. The results thus calculated agree with those determined experimentally.