Abstract: The federal government has long used solitary confinement, or segregation, in immigration detention to isolate immigrants from the general population with dire health consequences. The COVID-19 pandemic exacerbated the use of solitary confinement, with officials segregating individuals instead of providing them with necessary medical treatment. There is a general lack of transparency concerning the extensive use of solitary confinement, despite a 2013 federal directive that requires data collection about its use. Public records recently obtained through Freedom of Information Act requests and subsequent litigation reveal that individuals with mental illness, disabilities, and LGBTQ+ identities continue to be placed in solitary at high rates and often for prolonged periods, with some individuals held in solitary confinement for years. This Article documents the cruel and abusive use of solitary confinement in immigration detention for the last decade and its negative effects on mental and physical health. It draws on information obtained from federal agencies concerning the prolific use of solitary confinement in immigration detention and concludes by charting a path forward through executive action and legislative change at the federal and state levels.