We have reconstructed glacial-interglacial variations in Cibicidoides wuellerstorfi Δ13C and Δ18O in the southeastern Indian Ocean using depth transects of cores from off western and southern Australia. We compare these new results with published stable isotope records to constrain glacial-interglacial changes in Indian Ocean chemistry and circulation. The strong last glacial maximum (LGM) deep water 13C depletions previously observed for the northeastern Indian Ocean did not extend throughout the low-latitude glacial Indian Ocean. We observe only a small LGM Δ13C decrease off southern Australia, in marked contrast to the strong LGM 13C depletions observed in many cores from the Atlantic and western Indian sectors of the Southern Ocean. It is not yet clear whether the very low LGM Δ13C values in the deep northern and southwestern Indian Ocean are an artifact of surface ocean productivity or whether they reflect real gradients in deep water chemistry. ¿ 1998 American Geophysical Union