It is estimated that with appropriate treatment case fatality rates for children with severe malnutrition could be as low as 5% in both the community and in health-care facilities. However, over the past 50 years, case fatality rates for children with severe malnutrition treated as inpatients have remained largely unchanged at 20% to 30% for marasmus and up to 50% to 60% for kwashiorkor. According to WHO, 'the evidence for effective prevention and treatment is incontrovertible, but it is not put into practice'. As such, it is the feasibility of implementing guidelines in the context of the resource constrained health systems of developing country that is under question. Others have questioned the likelihood of achieving case fatality rates of 5% and the evidence that underlies the strategies for managing malnutrition within different settings. It remains unclear whether the lack of progress is a reflection of the initiatives available and the guidance provided, the ease of their implementation, a consequence of the changing nature of the problem, or a combination of all these factors. It is thought that no previous systematic reviews have assessed the effectiveness of different interventions to treat severe malnutrition among different populations and settings. As a consequence, a systematic review is needed to identify and synthesise all potentially relevant studies of interventions to treat severe malnutrition in children, using rigorous and recognised methodology. This study will add to the existing research by providing an up to date assessment of the existing evidence on the effectiveness of all initiatives, including the WHO guidelines. It will allow the evidence behind recommendations on how to treat severe malnutrition in different settings and the constraints relating to implementation of guidelines to be documented.