Densities, refractive indices and speeds of sound at 298.15, 303.15, and 308.15 K are reported for the binary mixtures ethyl acetate + 2-butanol and ethyl acetate + 3-methyl-1-butanol. Isobaric vapor-liquid equilibrium data at 101.3 kPa were determined for the ethyl acetate + 3-methyl-1-butanol system. Excess molar volumes, refractive index deviations and changes of speed of sound on mixing were calculated from experimental results and fitted with Redlich-Kister polynomials. VLE experimental data were satisfactorily tested for thermodynamic consistency by means of a modified Dechema test. The activity coefficients were correlated with the UNIQUAC, NRTL, and Wilson equations. The ASOG model was also used for prediction. (C) 2003 Elsevier B.V. All rights reserved.