The purpose of this study was to investigate the impact of a movement/rhythms program on mentally retarded individuals. Several authors purport that movement/rhythms is beneficial to the mentally retarded individual. However, there have been few data based inquiries into the actual effects of movement/rhythms programs. Furthermore, findings of those studies which have addressed this topic have lead to conflicting results. The problem addressed by this study was the previously unverified effect of movement/rhythms programs on mentally retarded individuals. A natural environment was used in the study to allow for a more in-depth investigation. The study was conducted at a middle school in Montgomery County with a group of 13 Educable Mentally Retarded adolescence for a period of 10 weeks. A case study approach was chosen to seek information and knowledge that would describe the effect of the program on EMR students' behaviors. The process of data collection utilized was a "type t" investigation and the primary instruments used were observational techniques, achievement measures and interviews. Triangulation of data from the administration of these instruments revealed that students benefited from the 10 week program in psycho-social and physical domains. A group analysis resulted in four distinct group types. Students who cooperated with others, initiated positive interaction with peers, and practiced the tasks to the point where they could peer teach successfully, were seen to benefit from the program in the psycho-social and physical domains. / Ed. D.