The inappropriate use of antibiotics has often been identified as a problem in effective health care delivery. High levels of antibiotics use, often clinically unnecessary, have led to a steady increase in drug resistance. Low-income countries, home to the majority of the world's population, are believed to have an important role in this phenomena. Effective intervention in these practices is often constrained by the paucity of information on determinants of antibiotic use. This review provides information from studies on the factors that influence the use of antibiotics by health providers, dispensers and community members in low-income countries. A proper understanding of these factors should be seen as a precondition for the development of more effective policies and programmes to address inappropriate antibiotic use. The review encompasses physicians' practices, the role of drug dispensers, and the influences on patterns of drug use across community members. Although a set of papers with useful research data was identified, probably the most important finding of the review was the scarcity of research. If interventions into antibiotic use are to be effective, future research must explore in more depth the socio-cultural rationality of antibiotic usage. The most productive approach would be to combine quantitative studies of the patterns of antibiotic use with the rich variety of qualitative methods like case simulations, focus group discussions, in-depth interviews, informal interviews, or illness diaries to explore determinants.Research programmes alone are unlikely to improve antibiotic use. Priority programme activities would include a carefully designed mix of activities by governments, health delivery systems, health training institutions, professional societies, pharmaceutical companies, consumer organisations, and international organisations. Strategies that lean too heavily on professional education are unlikely to result in large-scale or long-lasting improvement.