The high mortality rate among drug users, which is partly due to the HIV epidemic and partly due to drug-related accidental deaths and suicides, presents a major public health problem. Knowing more about prevalence, incidence, and risk factors is important for the development of rational preventive and therapeutic programs. This article attempts to give an overview of studies of the relations between substance abuse, suicidal ideation, suicide, and drug-related death. Research in this field is hampered by the absence of clear definitions, and results of studies are rarely comparable. There is, however, consensus about suicidal ideation being a risk factor for suicide attempts and suicide. Suicidal ideation is also a predictor of suicide, especially among drug users. It is correlated with an absence of family support, with the severity of the psychosocial dysfunctioning, and with multi-drug abuse, but also with requests for treatment. Every clinical examination of a drug user, not only of those who are depressed, should address the possible presence of suicidal ideation, as well as its intensity and duration.