Recent years have witnessed significant increase in numbers of older men imprisoned in England and Wales; a phenomenon experienced across the western world. Those aged fifty and over represent the fastest-growing demographic group in prison in England and Wales. This article summaries explanations for and implications of this increase and the characteristics, needs and lived experiences of this population, before critically reflecting on current policy and practice responses; and how responses highlight definitional and policy ambiguities around older prisoners. The article discusses a multi-agency initiative developed at one prison in northern England that recognised the uniqueness of older prisoners, modified regimes and changed physical environments. Impact is benchmarked against Her Majesty’s Inspectorate of Prisons four tests of a healthy prison, followed by discussion of findings and implications for policy and practice. The article argues for expanded collaboration to better manage challenges posed by older prisoners, supported by a national strategy.