The United States operates the world’s largest immigration detention system. On any given day, the country has some 30,000 people in administrative immigration detention at an estimated cost of nearly $150 a day. In 2016, the combined budget of enforcement agencies was $19 billion. The country’s sprawling detention estate counts on some 200 facilities, including privately operated detention facilities, local jails, juvenile detention centres, field offices, and euphemistically named “family residential centres.” The country has also supported the detention of migrants and asylum seekers in neighbouring countries.