Phase and chemical equilibria in the quaternary water + ethanol + ethanoic acid + ethyl ethanoate system was measured in a modified Dvorak and Boublik still. In total, 39 experimental points at 348.15 K were determined. The experimental data were correlated by means of the maximum likelihood procedure by using the NRTL model. Binary model parameters for the four nonreacting binary subsystems were obtained from available experimental vapor-liquid equilibrium data by using either the Hayden-O'Connell or Marek-Standart correction to account for the nonideality of vapor phase. NRTL parameters for the water + ethyl ethanoate and ethanol + ethanoic acid systems were estimated from the global optimization based on the quaternary data. The results obtained from the correlation show a good agreement of calculated and experimental data. The three-dimensional phase diagrams for the quaternary system have been constructed with use of transformed compositions.