In many parts of Asia, critics have noted the common but hitherto under-researched practices of detaining victims of human trafficking in semi-carceral institutions or ‘shelters’, in the name of victim protection and rescue. Although the formal justification for immigration detention and ‘protective custody’ may be different, there are clear parallels between the experience of trafficking victims in semi-carceral institutions and what Kalhan has termed ‘a quasi-punitive system of immcarceration’. This article seeks to add to the critical work on the changing nature and harms of immigration control by exploring the logic and practices of protective custody in Asia. How can we make sense of the regulatory purposes performed by semi-carceral institutions for trafficking victims? What do we know about women and girls’ experiences of protective custody in South and South-East Asia? In what ways does the dominant anti-sex trafficking discourse of ‘protection’ and ‘rescue’ intersect with gendered notions of belonging and citizenship? And, ultimately, what can a study of gendered carceral practices tell us about the problems and paradoxes of trafficking control?