The Merchants' Quay Project: Drugs/HIV Service was set up to help prevent the spread of HIV through drug-use and related behaviour and to provide non-judgmental care and support to drug users with HIV and their families. Thus the twin problems of drug use and HIV provide the background and context to the project. This chapter summarises some general information on HIV, ADDS and drug use in Ireland. Section 1.2 summarises statistical information on the characteristics of known HIV+ cases in Ireland while section 1.3 analyses statistical trends in the characteristics of cases and deaths from AIDS in Ireland between 1982 and 1992. Section 1.4 provides a brief overview of the data on drug use in Ireland. The problems associated with HIV and drug use are partly related and the policy response has tended to treat them jointly. This policy response is examined in section 1.5. Finally in section 1.6 there is a brief summary of the key findings to emerge in the chapter.