Abstract: This Selected issue starts off by reviewing the available data on drug use among prison populations in Europe, focusing on injecting drug use and other health risk behaviours. Major health risks for drug-using prisoners, including blood-borne infections and infections that can affect all prisoners equally, such as tuberculosis, are discussed. Also mentioned is the role of prison environments, where overcrowding and unsanitary conditions are not uncommon, and the higher-than-average occurrence of psychiatric problems among prisoners. The first section concludes by describing the increased risk of death among prisoners, both in custody and after release. The second part of the report focuses on responses to the health needs of drug-using prisoners in European countries. The study looks at how the internationally recognised rights of prisoners and the European and international rules that set standards for the care of prisoners apply to those with drug problems. The administration of prison healthcare in European countries is examined, and national policies are reviewed. This is followed by an overview of the available information on drug-related service provision in Europe, from prison entry to prison release, addressing counselling, treatment of drug dependence and the prevention of infectious diseases and drug overdose.