Isobaric vapor-liquid equilibrium (VLE) data for a wide range of temperatures, pressures, and compositions were measured for the methanol + N-methyldiethanolamine (MDEA) + water and methanol + 2-amino-2-methyl-1-propanol (AMP) + water ternary systems. The vapor pressure of pure AMP and two binary subsystems, MDEA + water and methanol + AMP, was also studied. For MDEA + methanol, MDEA + water, AMP + methanol, and AMP + water, the nonrandom two-liquid (NRTL) parameters were fitted using all our experimental data and VLE and H-E data taken from the literature.