Vapor-liquid equilibrium at 94 kPa has been determined for the binary systems 2-butanone + heptane and 2-butanone + oxolane. The system 2-butanone + heptane deviates strongly from ideal behavior and presents an azeotrope that boils at 348.4 K and contains 75.0 mol % 8-butanone. The system 2-butanone + oxolane behaves like a regular solution and does not have an azeotrope. The activity coefficients and boiling points of both binary systems were well-correlated with its composition by the Redlich-Kister, Wohl, Wilson, UNIQUAC, NRTL, and Wisniak -Tamir equations.