Mango slices (1 and 2 mm thickness) were dried by using the Refractance Window™ (RW) technique with the water bath temperature set at 92 _C. Drying kinetics, water activity, and color change were determined and compared with those obtained by drying the slices in a tray dryer at 62 _C and an air velocity of 0.52 m/s. At 1 h, moisture contents of 0.013 (for 1 mm sample) and 0.048 (for 2 mm sample) kg water/kg dry solid for RW, and 0.966 (for 1 mm sample) and 3.614 (for 2 mm sample) kg water/kg dry solid for tray drying were obtained and water activity was less than 0.5 for RW and close to 0.97 for tray drying. The tray dryer took 4 h to reach results similar to those of RW at 1 h. The samples dried by RW exhibited diffusivities of 4.40 _ 10_10 (for 1 mm sample) and 1.56 _ 10_9 (for 2 mm sample) m2/s, which are larger than those exhibited by the air-dried samples, 2.08 _ 10_11 (for 1 mm sample) and 6.83 _ 10_11 (for 2 mm sample) m2/s.