People sharing an environment, even with different patterns of social structure and movement, will also share many of the same health and environmental risks. In a prison or jail context, therefore, there may be signi cant overlap in risks – and health protective factors – between prisoners and prison staff. Thus, it makes no sense to consider the health needs of prisoners without realizing that in many instances they are closely connected with occupational health and safety issues of prison staff, and vice versa. In a close and closed community, infectious diseases will spread with little distinction between the inmates and the custodial staff. Further, where the environment is stressful, that stress will be manifested in both the inmates and the staff, and where it is unsafe, the lack of safety will extend to staffprisoner as well as prisoner-prisoner interactions. In addition, environmental hazards will impact both staff and inmates, whether through cold, heat, noise, poor ventilation or environmental toxins such as asbestos or lead. Inmates and staff breathe the same air, walk in the same buildings, touch the same objects, and often suffer the same stresses of the psychological and physical environment. Sometimes they will eat food prepared in the same kitchens by the same staff or inmates. From a physical and psychological health perspective, if a prison is an unhealthy environment for inmates, it will also be unhealthy for staff. Thus, it makes no sense to consider the health needs of prisoners without realizing that in many instances they are closely connected with occupational health and safety needs of prison staff, and vice versa.