Liquid-liquid equilibrium data are presented for mixtures of 2,6-dimethyl-4-heptanone (diisobutyl ketone) + an alkanol + water at 298.15 K. The alkanols are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, and 2-methyl-2-propanol. The addition of ethanol, 2-propanol, or 2-methyl-2-propanol is found to increase the solubility of water in the diisobutyl ketone more than the other alkanols. The relative mutual solubility of methanol ana ethanol is higher in the water layer than in the diisobutyl ketone layer. The converse is true for the other alkanols. Three three-parameter equations have been fitted to points on the binodal curve. The results are compared and discussed in terms of statistical consistency. The NRTL and UNIQUAC models were used to correlate the experimental results and to calculate the phase compositions of the ternary systems. The NRTL equation fitted the experimental data better than did the UNIQUAC equation, and the average root mean square deviation phase composition error was 0.013 for the NRTL model and 0.046 for the UNIQUAC model.