Imprisonment is a feature of the penal system of every country in the modern world, and its use has been growing rapidly over many decades. Today, well over ten million people are incarcerated worldwide, of whom around half are in prisons in the United States, China, Russia and Brazil. Much as prisons are an almost entirely taken-for-granted part of the machinery of the modern state, there remain many highly contentious aspects to the use of imprisonment as a tool of criminal justice policy. In much of the world, one finds poor and degrading conditions of detention, lack of due process in the imposition of custodial terms, evidence of imprisonment’s limited efficacy as a means of deterring crime or rehabilitating offenders, and enormous costs to the public purse associated with large and rising prison populations.

This short volume offers a comprehensive yet concise account of prison populations worldwide, alongside discussion of the ethical challenges and imperatives of the use of imprisonment in the twenty-first century and, finally, a brief consideration of what an alternative future for penal policy might look like.

The book has three main sections. Section I provides a descriptive account of prison populations around the globe. This includes comparisons of regions and jurisdictions with the highest and lowest prison population levels, an overview of numbers of women in prison and numbers of prisoners held in pre-trial detention or on remand, and commentary on trends in prison populations worldwide and in individual jurisdictions. In addition to presenting international prison statistics – drawn from the World Prison Brief online database – the section incorporates discussion of factors that underlie diversity and change in levels of imprisonment worldwide.

Section II begins with a discussion about what constitutes deprivation of liberty and what rights are forfeited as a consequence. It then explains why it is important to consider the use of imprisonment within an ethical context and goes on to propose that this can be provided by basing the practice of imprisonment on the human rights standards which have been agreed by the international community. The section then examines in detail how these standards can be applied to the treatment of prisoners and ends with a response to some of the current challenges to an ethical approach to the use of imprisonment.