This overview of recent research on health behaviour change in developing countries shows progress as well as pitfalls. In order to provide guidance to health and social scientists seeking to change common practices that contribute to illness and death, there needs to be a common approach to developing interventions and evaluating their outcomes. Strategies forming the basis of interventions and programs to change behaviour need to focus on three sources: theories of behaviour change, evidence for the success and failure of past attempts, and an in-depth understanding of one’s audience.