Background: The various levels of severity are defined on the basis of adaptive functioning, and not IQ scores, because it is adaptive functioning that determines the level of supports required. Moreover IQ measures are less valid in the lower end of IQ range. Mental retardation is a disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. Although MR is not treatable, many associated impairments are amenable to homoeopathic intervention and therefore benefit from early identification. Objectives: 1. To study different clinical presentations of mental retardation. 2. To evaluate the usefulness of homoeopathic medicines in the improvement of adaptive behaviors of mentally retarded children. 3. To evaluate the usefulness of homoeopathic medicines in the improvement of IQ of mentally retarded children.