OBJECTIVE:to learn what primiparous mothers in Lusaka, Zambia know about human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), mother-to-child transmission (MTCT) of HIV, and breast feeding. DESIGN:qualitative interviews analysed by thematic manifest content analysis. SETTING:postnatal wards at Lusaka University Teaching Hospital. PARTICIPANTS:14 primiparous mothers were interviewed. FINDINGS:1 year after implementation of the prevention of MTCT programme in Zambia, the majority of the women interviewed lacked basic knowledge about MTCT. They did not know that HIV is present in breast milk and that it is a source of transmission. Few mothers had been informed about breast feeding, correct attachment and ways of avoiding breast infection. The mothers seemed to be uncertain about what HIV actually is, and they preferred to talk about MTCT and safe breast feeding rather than HIV/AIDS in general, which was the main reason for their participation in the study. According to the mothers, the most effective way of preventing transmission of HIV to the unborn baby was a single dose of nevirapine. Many believed that treatment is equal to cure and gives the baby full protection. The overall feeling of mothers was that they had not received information and support from the antenatal clinics and postnatal wards. The more traditional women preferred not to discuss these issues with their friends, their husbands or their families, which may make it more difficult to spread information and encourage couples to make decisions about their and their baby's future. CONCLUSION:these findings suggest that primiparous mothers and their families need more education about MTCT of HIV. The mothers also need basic education about breast feeding and how to avoid breast injuries. The main reason for mothers' poor knowledge may be that health workers do not have the necessary information. There seems to be a need for training in breast-feeding and baby-feeding counselling in the context of HIV in order to promote exclusive and safe breast feeding. As such, further research about health workers' knowledge and methods of teaching is required.