Strategies for preventing transmission of human immunodeficiency virus (HIV) include ensuring that individuals have adequate knowledge of how HIV infection can be prevented and encouraging behaviours that decrease risk of HIV infection. In addition, there is evidence that early and appropriate management of other sexually transmitted disease is effective in reducing HIV transmission. Programmes and projects promoting prevention of HIV transmission should be evaluated periodically for their effectiveness. Between March and September 1995, ten prevention indicators developed by the WHO Global Programme on AIDS were used to establish a baseline measure for evaluating the effectiveness of the Ethiopian AIDS control programme. The indicators were measured using a structured population survey, through record review and key informants, structured observation and interview in health care facilities, and through a serosurvey among antenatal clinic attenders. The following results were found: promoting knowledge of preventive practices was successful; a relatively high proportion of young male adults had sexual risk behaviour; poor condom availability outside Addis Ababa, the capital; and very weak STD case management. The prevalence of syphilis and HIV were 8.8% and 13.6%, respectively, among pregnant women aged 15-49 years. These results should serve as a baseline for repeat surveys to assess the effectiveness of HIV prevention programmes in Ethiopia.