Abstract: Political economy offers unique tools and perspectives for analyzing the growth of immigration detention systems. This approach highlights changing economic structures, the winners and losers of policy changes, and the motives of social actors involved in affecting political decisions. Ultimately, assessments of the political economy of detention point to a key challenge that is common to countries across the globe: how economic insecurities of host populations translate into xenophobia and ethno-nationalist demands for more deportations, detentions, and walls. On the other hand, similar factors that have undermined the rationale for private prisons may also empower efforts to limit the growth of immigration detention—namely, the high cost in both monetary and social capital of locking up people who could otherwise be productive members of society.