Today it's common for a prisoner in the U.S. prison system to spend time in solitary confinement: twenty-three hours a day in featureless cells, with no visitors or human contact. Sometimes this lasts for years on end, and prisoners are held at administrators’ discretion. Keramet Reiter tells the history of one “supermax,” California’s Pelican Bay State Prison, whose extreme conditions recently sparked a statewide hunger strike by 30,000 prisoners. The product of fifteen years of research in and about prisons, this book provides essential background to a subject now drawing national attention.