Densities, viscosities and refractive indices of 4-diethylamino-2-butanol + water mixtures were measured over the entire concentration range of 0-1 mole fraction and temperature range from 298.15 to 343.15 K. Excess molar volumes, viscosity deviations, and molar refraction changes were calculated from the measurement results and correlated as a function of the mole fractions. Various models were used for correlation with the measured data. Out of these, the Redlich-Kister equation was the most suitable model that correlated best with experimental data. The percent absolute deviations obtained with this model were 0.03% for density, 0.88% for viscosity and 0.009% for refractive index. (C) 2008 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.