Compared to elsewhere in the UK, drug policy in Northern Ireland has for the most part failed to incorporate harm reduction strategies. In light of the conservative drug policies, the purpose of this study was to investigate the nature and extent of risk behaviours among injecting drug users (IDUs) in Northern Ireland. Data for this study were drawn from in-depth interviews with 39 IDUs in Northern Ireland. The findings suggest that most IDUs engage in extensive risk behaviours that pose risk for HIV, Hepatitis B and C, and other infectious disease. Moreover, these risk behaviours are linked to the scarcity of new needles and a general lack of knowledge about injection practices that reduce risk for infectious disease. These findings are discussed in the context of conservative drug policies.