Isothermal vapor-liquid equilibria were measured for the binary systems, 1,2 dichloroethane-n-heptane, 1,2 dichloroethane-n-butanol, and n-heptane-n-butanol, at 25 ℃, 35 ℃, 45 ℃, 55 ℃, 65 ℃ and 75 ℃ using the total pressure method. Vapor compositions were obtained by the Wilson equation and the Redlich-Kister equation. For these binary systems, isobaric vapor-liquid equilibria were estimated by cross plotting isothermal vapor-liquid equilibria data which were obtained from the total pressure method. Also isobaric vapor-liquid equilibria in the ternary system of 1,2 dichloroethane-n-heptane-n-butanol were estimated from the results for the corresponding binary systems by using one parameter Wilson equation. The predicted data were found to be in a good agreement with experimental data.