Experiments have been conducted with water/2-propanol mixtures under reduced gravity, normal gravity and high gravity in order to investigate Marangoni effects and their interaction with the gravitational effect in the pool boiling of binary mixtures. The system pressure was subatmospheric (similar to 8 kPa at 1 g(n)) and the bulk liquid temperature varied from low subcooling to near saturation. The molar concentrations of 2-propanol tested were 0.015, 0.025 and O.1. The reduced and high gravity experiments were conducted aboard a DC-9 aircraft at NASA Lewis Research Center. Boiling curves were obtained both for high gravity (similar to 2 g(n)) and reduced gravity (similar to 0.01g(n)) and the duration of both the:high gravity and reduced gravity period was approximately 20 s per parabola. For each concentration of 2-propanol, the critical heat flux (CHF) has been determined for normal and reduced gravity conditions. The present experimental data are compared with the available predictive correlations for binary mixture boiling heat transfer and critical heat flux conditions. Comparison of boiling curves obtained from the experiment under 2-g(n), 1-g(n) and reduced gravity indicates that the boiling mechanism in-these mixtures is nearly independent of gravity. The CHF values determined under reduced gravity conditions for each concentration did not change significantly from those measured under 1-g(n) conditions. The results also indicate that the Marangoni mechanism is strong enough in these mixtures to sustain stable nucleate boiling under reduced gravity conditions.