A paucity of data limits our understanding of standard of living and inequality in Irish society in the nineteenth century. The long-term effects of the Great Famine are difficult to ascertain due to an absence of individual-level census records. And the economic and social effect of the great penal and judicial reforms of the nineteenth century are not well quantified. The analysis of anthropometric data on Irish prison inmates may provide a solution. Prison registers, held at the National Archives of Ireland and the Public Record Office of Northern Ireland, are rich in detail, providing information on age, crimes committed, dates sentenced and released, recidivism, religion, height, literacy, marital status and occupation. The aim of this project is to collect a representative sample of registers covering prisons in Dublin, Belfast, Cork and Londonderry, for the entire nineteenth century. Data on individual prisoners will not only enable us to track the evolution of standards of living across the century, but statistical analysis of these data will enable us to determine the causes of change.