The U.S. Program for the International Assessment of Adult Competencies, National Supplement Prison Study (PIAAC Prison:14) is a study that is part of the Program for the International Assessment of Adult Competencies (PIAAC) program; program data is available since 2012 at http://nces.ed.gov/pubsearch/getpubcats.asp?sid=113. PIAAC Prison:14 (http://nces.ed.gov/surveys/piaac/national_supp.asp) is part of the National Supplement and draws from a sample of 1,200 inmates aged 18 to 74 years-old currently detained in State, Federal, or private prisons in the United States. The direct assessments of literacy, numeracy, and problem-solving in technology-rich environments are the same for the adults in prison. The background questionnaire was tailored specifically to address the experiences and needs of this subgroup. For example, the background questionnaire asks about activities in prison, such as participation in academic programs and ESL classes, experiences with prison jobs, and involvement in non-academic programs such as employment readiness classes.