Total vapour pressure measurements made by the modified static method for the ternary system hexane-methanol-acetone and constituent binary system hexane-methanol at 313.15 K are presented. The alcohol high dilution region of the methanol-hexane system is thoroughly studied. The different expressions for GE suitable for correlation of these data are tested; the systems hexane-acetone and methanol-acetone, published previously, have been also rediscussed from the point of view of the present ternary system. The prediction of ternary VLE from constituent binaries is studied. Our results are compared with literature data.