In criminal justice, particularly in North America, correction, corrections, and correctional, are umbrella terms describing a variety of functions typically carried out by government agencies, and involving the punishment, treatment, and supervision of persons who have been convicted of crimes. These functions commonly include imprisonment, parole and probation. A typical correctional institution is a prison. A correctional system, also known as a penal system, thus refers to a network of agencies that administer a jurisdiction's prisons and community-based programs like parole and probation boards; this system is part of the larger criminal justice system, which additionally includes police, prosecution and courts. Jurisdictions throughout Canada and the US have ministries or departments, respectively, of corrections, correctional services, or similarly named agencies.

Corrections is also the name of a field of academic study concerned with the theories, polices, and programs pertaining to the practice of corrections. Its object of study includes personnel training and management as well as the experiences of those on the other side of the fence — the unwilling subjects of the correctional process. Stohr and colleagues write that "Earlier scholars were more honest, calling what we now call corrections by the name penology, which means the study of punishment for crime."