Across the globe, many countries are experiencing prison overcrowding despite overall reductions in crime. Along with an increase in demand, budget cuts and understaffing have increased the pressure upon prison officers, who face a number of occupational and organisational threats to their wellbeing such as verbal and physical aggression, high workload and work‒life conflict. United Nations standards for the treatment of prisoners (the Nelson Mandela Rules) highlight the importance of prison staff for the “proper administration” of prisons, requiring resourcing that enables staff to perform well. It is important to consider the wellbeing of prison officers for moral as well as for operational reasons, as this has been shown to influence their attitudes to rehabilitation and their treatment of prisoners. In this chapter we review research that has examined antecedents and consequences of wellbeing in prison officers, and make recommendations to address the challenges.