Patrick L. O'Daniel Unit is a Texas Department of Criminal Justice prison housing female offenders in Gatesville, Texas. The unit, with about 97 acres (39 ha) of land, is located 4 miles (6.4 km) north of central Gatesville on Farm to Market Road 215. The prison is located in a 45-minute driving distance from Waco. In addition to its other functions, O'Daniel Unit houses the state's female death row inmates.

The Texas Department of Criminal Justice (TDCJ) is a department of the government of the U.S. state of Texas. The TDCJ is responsible for statewide criminal justice for adult offenders, including managing offenders in state prisons, state jails, and private correctional facilities, funding and certain oversight of community supervision, and supervision of offenders released from prison on parole or mandatory supervision. The TDCJ operates the largest prison system in the United States.