This is a detailed manual giving a step by step approach to undertaking the pharmacovigilance of antiretrovirals. It is intended to be a source of practical advice for Pharmacovigilance Centres and health professionals involved in HIV/AIDS prevention and treatment programmes. A number of WHO publications are available that provide a background to pharmacovigilance and, as far as possible, that material will not be repeated here. Health officials, planners, the staff of Pharmacovigilance Centres, public health teams and all health workers should become familiar with these publications, which are: • Safety of Medicines: A guide to detecting and reporting adverse drug reactions