This report presents the findings of a qualitative study carried out in Maputo, Mozambique, among women engaged in cross-generational transactional sex. Cross-generational sex is contributing significantly to the spread of HIV/AIDS in Mozambique and as such is a key area for behaviour change interventinos, although few organisations are currently addressing the issue. The study reveals thta young women engaged in cross-generational and transactional sex have a complex sexual network involving multiple partners, including both transactional and non-transactional relationships. The study was carried out between October and November 2004, using the PEER (participatory ethnographic evaluation and research) method. PEER is an innovative approach to programme research, evaluation and design, based upon training members of the target group (peer researchers) to carry out in-depth qualitative interviews among their peers. Twenty young women in the age group 16-25 years, living in and around central Maputo were recruited as peer researchers. Each peer researcher interviewed three peers and conducted three separate interviews with each peer, with a total of 180 interviews carried out.