Is changing sexual behaviour an effective tool for reducing the levels of HIV infection? If so, how can behavioural change programmes best be implemented at community level? Research by the Medical Research Council (UK) Programme in Uganda explores the implementation of a randomised controlled trial (RCT) set up to study the effects that community Information, Education and Communication (IEC) and improved management of sexually transmitted diseases (STDs) can have on STD and HIV infection rates on a rural population in south west Uganda.