Direct current measurements and geostrophic transport estimates, using hydrographic data collected in the eastern Indian Ocean, reveal that during October 1987 the South Equatorial Current carried about 22¿106 m3/s in the upper 500 m of the water column. The Indonesian throughflow from the Pacific Ocean supplied about half of that transport; the other half came from the recirculation of the southern hemisphere subtropical gyre. The mixing of the Indian Central Water and the Australasian Mediterranean Water in the thermocline occurred mainly off the northwest Australian shelf due to enhanced mesoscale current variability in that area. ¿ American Geophysical Union 1996