The aim of this research was to explore people’s knowledge, attitude, behaviour and practice towards HIV/AIDS and sexual activity in rural Kenya, where HIV is widespread. The study community was located in south-eastern Kenya, 50 km north of Mombassa, and had an estimated population of 1500. Subjects aged between 16 and 49 were recruited using a stratified cluster-sampling method and they completed self-administered questionnaires.Almost all respondents knew the word ‘HIV’. Around 50% knew of a person living with HIV. About 80% gave ‘death’ or ‘fear’ as words representing their image of AIDS. With regard to sexual activity, the distribution of answers to the question ‘how many partners have you ever had in your life’ was bimodal in males but had only one peak in females, indicating that some men have a large number of sexual partners in their lifetime. First sexual intercourse was at around 12–13 years for both sexes, but female teenagers were more sexually experienced than their male counterparts.