The Demographic and Health Surveys (DHS) for Kenya, Tanzania, Uganda and Zambia provide information on how people react to HIV/AIDS: knowledge acquisition; (self-declared) strategies for avoiding HIV; age at first intercourse; monogamy; abstinence; having been tested and wanting to be tested. A subsample of respondents are marriage partners allowing the analysis of assortativeness in behaviour. When possible, DHS findings are related to the epidemiological literature. Throughout, attention is given to the internal consistency of the surveys and their consistency with epidemiological studies. Suggestions are made for the improvement of DHS-type surveys.