The study shows that in Hong Kong there is a reliance on criminal justice sanctions to address the problem of irregular migration. This has led to a massive increase in the arrest and detention of migrant women, primarily those Chinese women who have crossed the border from mainland China to engage in sex work in Hong Kong. Given that the length of imprisonment of the majority of female immigration violators is relatively short (an average period of 40 days), there is little provision for rehabilitation and training in the overcrowded penal institutions. Thus, imprisonment of these women merely "warehouses" the unwanted poor women struggling to survive economically. There is little evidence that the incapacitation of unwanted migrant women can solve the social problem of migratory sex work and socioeconomic disparities within China. The primary data for this study were collected during an exploratory field trip to Hong Kong between January and April 2004, supplemented by interviews and documentary investigation between November 2005 and February 2006. This involved the examination of relevant official reports and internal police and Immigration Department statistics, along with indepth interviews with criminal justice practitioners, activists in a sex workers' concern group, and academic researchers who have conducted immigration studies. 1 table and 69 references