The prison industry in the United States is massive and growing. Since 1970, the number of incarcerated people in the U.S. has increased by 700 percent, to the point that the U.S. prison population is the largest in the world both per capita and in total numbers. As of 2019, there are an estimated 2.3 million people behind bars and 4.5 million people on probation or parole. The estimated cost of the U.S. mass incarceration system is $182 billion a year, with hundreds of private companies competing for government contracts.

The most visible and publicly debated corporate involvement in the prison industry is through private prisons, i.e. prisons that are owned, managed, or operated by private for-profit companies instead of by government agencies. As of 2019, an estimated 8.2 percent of people in U.S. federal and state prisons are incarcerated in private prisons, and nearly three-quarters of all people in immigration detention are held in privately-run facilities.

However, private prisons are just the tip of the iceberg for prison profiteering. Whether public or private, all prisons, jails, and immigration detention centers rely on for-profit companies for their operations, as nearly every aspect of the prison industry has been privatized to a certain degree.