The work of the prisons and probation services is commissioned by the National Offender Management Service. NOMS was created following a review of correctional services in England and Wales. The review identified improvements needed in prisons and probation and also identified changes in sentencing that had led to increases in prison and probation workloads. NOMS aims to provide a more coherent end to end service for offenders and the public, managing offenders across the entire life of their sentence. NOMS also aims to use the knowledge and expertise of the public, private and third sectors to provide solutions to tackling offending behaviour.

NOMS is part of the Ministry of Justice. The Ministry has responsibility for administration of the courts, tribunals and legal aid and by combining this with responsibilty for prisons, probation, criminal law and sentencing policy, the Ministry manages the delivery of justice from an offender's first appearance in court, right through to their rehabilitation and release.