The media and generalist scholarly work have created a conventional wisdom that China's one-child policy is the driver of the country's skewed sex ratio and so should be relaxed in order to ameliorate the imbalance. However, we show through historical, domestic and international comparisons that son preference, which we treat as an observable and measurable variable made up of labour, ritual, inheritance and old-age security practices and policies, is crucial to explaining the imbalanced sex ratio at birth. China's sex ratio cannot fully normalize without addressing son preference.
