Controversies over the inclusion of growth monitoring in child health programmes have grown sharper and more numerous as experience accumulates from developing countries. Most criticisms have focused on the poor implementation of growth monitoring and its complementary activities of health education and treatment of illness. This review assesses the evidence for the importance of growth monitoring's contribution to various programme objectives: focusing health interventions on at-risk children, promoting community development, and providing information for nutrition surveillance and programme management. The costs of growth monitoring are largely unknown, although cost-benefit information from a few programmes is presented. Taking into account the low sensitivity and specificity of anthropometry to detect risk of dying, inaccuracies in weight measurements, low and non-representative coverage, and the high incidence of growth faltering in young children, the benefits of using growth monitoring as a screening mechanism appear to be few. The main potential appears to be as a catalyst for action on the part of the mothers, community and health service. However, the claims made for growth monitoring as an important element to increase the effectiveness of health care and education, increase utilization of services, and promote participation and empowerment in health care have not been supported by well-designed studies. The supposed potential of growth monitoring will not be realized unless attention is paid to pre-eminent issues of planning, training, resources, supervision, management and evaluation in child health services.