Prisons run on paper. The rhythms of the day and year are managed through an elaborate infrastructure of forms, ledgers, and apps that has remained remarkably unchanged over the past century. Accumulating paperwork seeks to document, manage, and control the constant change that defines prison life – from the routine of admitting new arrivals to the ongoing process of maintaining old buildings. At the same time, the fragility of these ageing documents underscores the experience of prison and the difficulties of understanding life inside.