Sex preferences for children, and their behavioral manifestations, take form within a complex lattice of social and environmental contexts. Perhaps the most sweeping generalization of social context is the family system, describing a cluster of interrelated family processes. It has been argued, for example, that son preference of the Han Chinese is inherent in the patrilineal joint family system common across much of Asia (Skinner 1997). It would follow then, that the family systems of many southern Chinese minority nationalities, which share characteristics that accord a higher value to females, would produce a pattern of sex preference divergent from the Han pattern. Evidence from an isolated Li community in Hainan Island is generally consistent with this proposition: juvenile sex ratios are roughly even and sex ratios at higher parities appear biased in favor of females. However, even within this small community, sex preferences are not homogeneous. The observed disparities suggest that sex preferences are sensitive to local variations in economic context