The purpose of this article is to review the research status of illicit drug use and its data sources in Latin America, with particular attention to the research that has been produced in the past 15 years in epidemiology of illicit drug use services utilization, and relationship between HIV and drug use. This article complements the series of articles that are published in this same volume which examine drug abuse research (epidemiology, prevention, and treatment) and HIV prevention in Latinos residing in the United States. This review resulted from extensive international and national searches using the following databases: Current Contents Connect, Social and Behavioral Sciences; EBSCO; EMBASE(R) Psychiatry; Evidence Based Medicine (through OVID); Medline, Neurosciences, PsychINFO, Pubmed, BIREME/PAHO/WHO--Virtual Health Library, and SciELO. Papers selected for further review included those published in Spanish, English, and Portuguese in peer-reviewed journals. From the evidence reviewed, it was found that the published research literature is heavily concentrated on descriptive epidemiologic surveys, providing primarily prevalence rates and general information on associated factors. Evidence on patterns of service delivery and HIV prevention and treatment is limited. The cumulative scope of this research clearly indicates variability in quantity and quality of research across Latin American nations and the need for greater uniformity in data collection elements, methodologies, and the creation of international collaborative research networks.