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Surface temperatures of the hand, blood pressure and heart rate were monitored on 17 highland Quechua Indian males, 15 Indian females and 6 white males during hand immersion for 20 minutes in water at 4° C. Cold-induced vasodilation was recorded and comparisons were made of reactive hyperemia produced by a brief period of arterial occlusion. Indian females maintained warmest skin temperatures and showed more pronounced cold-induced vasodilatory and reactive hyperemia responses. Females also displayed the least increases in systolic cold pressor response and heart rate during cold water immersion. White males were the least cold tolerant. The results of these and prior tests of Andean Indians suggest that members of this population are better able to tolerate local cold than are whites. Indians appear to employ differentially at least two modes of circulatory control of blood to the surface. The relative importance of these two modes of control is dependent upon the severity of the cold stress.