This article examines the impact of imprisonment on citizenship. It identifies how civil, political and social rights are circumscribed with a sentence of imprisonment, and scrutinizes to what extent citizenship is limited for prisoners. Drawing on recent developments in England and Wales, it contends that citizenship has been eroded, not as a ‘collateral consequence’ of imprisonment, but rather as a determined penal policy. The boundaries of punishment have become blurred, moving from criminal justice institutions, and extending towards what is termed civil and political penality. Finally, it argues that, because citizenship in prison is inevitably framed around the differences between freedom and captivity, prisoners respond to the constraints of imprisonment through alternative ways of expressing their citizenship.