Homelessness in the US is a humanitarian crisis, with more than 771 000 individuals experiencing homelessness in a single night in 2024, representing a 38% increase from 2023. Homelessness is also a health crisis. At least one-third of our nation’s homeless population are unsheltered, exposing them to extreme heat and cold; two-thirds have used illicit drugs regularly; and nearly 50% have a mental illness. The combined effect of substance use disorders (SUDs), serious mental health disorders, and certain chronic health conditions that are associated with homelessness leads to premature mortality. This population dies 30 years earlier than other US residents, at the mean age of death in the US in 1900. Of the interventions that have been tested and implemented, helping people into stable housing without precondition of sobriety, otherwise known as the Housing First model, is a compassionate way to decrease homelessness, reduce health care use, and possibly improve health outcomes. Although the Housing First model previously received broad bipartisan support, the Trump administration appears ready to abandon this approach. Doing so would have grave consequences for the health of the US.