The "CLAPSEN" approach was developed at the Hospital Materno Infantil German Urquidi in Cochabamba, to provide a global response for the study and treatment of childhood malnutrition. "CLAPSEN" is short for Clinical, Laboratory, Anthropometry, Psychology, Sociology, Nursing (Enfermera in Spanish) and Nutritional care. Most of the malnourished children admitted to Cochabamba Hospital are from poor families, more than three quarters of whom have only recently arrived in the city. Acute malnutrition is just one of the manifestations of a generally unfavorable environment. Malnutrition should not be considered as a simple deficiency in energy, protein or micronutrients, but rather as a multi-deficiency syndrome, also involving a lack of basic health and social care. This study demonstrates that malnourished children display a considerable degree of psychological retardation and of immune system depression. After five weeks of rehabilitation, the children were considered to have recuperated physically, as assessed by anthropometry, but not psychologically, as assessed by the adapted Dewer Score, or immunologically, as shown by the size of the thymus or the extent of maturation of lymphocytes. This strategy was not designed as a long-term approach for treating malnutrition, but rather as a research project to characterize the children arriving at the hospital, to determine the reasons for their malnutrition and to identify strategies that could be implemented earlier by health centers of social services, to prevent deterioration in the condition of these children to severe malnutrition requiring hospital admission. We believe that, in this Latin American context, in which the rate of acute malnutrition is low, the hospital should continue to be involved in the treatment of severely malnourished children with associated diseases. The child's stay in hospital should be short and once the child has recovered clinically, he should be sent home. In light of the observed levels of social deprivation, psychosocial and immune deficits, there appears to be a need for continued support for the family, to ensure the full recovery of the child and to prevent relapses.