This publication has been compiled within the framework of Correlation, a European Network on Social Inclusion and health (www.correlation-net.org). This network focuses on the development and implementation of effective strategies to provide health and social services to socially marginalised and vulnerable populations. In general terms, the network supports the harm reduction approach as a humanistic, evidencebased and cost-effective strategy. One of the aims of the network is to contribute to a better understanding of the European dimension of marginalisation, health and social inclusion.