The tie-lines and liquid-liquid equilibria are presented for mixtures of an alkanol + diisopropyl ether + water at 25-degrees-C. The alkanols are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol and 2-methyl-2-propanol. Three three-parameter equations have been fitted to the results. These equations are compared and discussed in terms of statistical consistency.