This report contains the recommendations of a WHO Expert Committee convened to consider the prevention and control of schistosomiasis and soil-transmitted helminth infections. Although these infections remain major public health concerns in many parts of the world, particularly in the poorest developing countries, cost-effective solutions are both available and deliverable. The report reviews the burden of disease, its impact on both health and development, the substantial benefits of treatment, and the safety, efficacy and ease of administration of available anthelminthic drugs. Similarities in the population at risk and in the tools required to combat the problems have prompted moves towards a combined approach to the control of schistosomiasis and soil-transmitted helminthiasis. Such an approach relies largely on epidemiological surveillance, health education, improvements in hygiene and sanitation, and--above all--regular treatment of high-risk groups, particularly school-age children. The report focuses on how these various elements can be achieved, emphasizing the potential of the school system for drug delivery and health education and the opportunities for integration of control activities with existing health programmes. It also stresses that the cost of recommended anthelminthic drugs has now fallen to a level at which it should no longer deter Member States from making treatment widely available in endemic areas. The recommendations of the Expert Committee provide clear and strategic guidance on the implementation of control measures and on ensuring their sustainability.