Background. Individuals with intellectual and developmental disabilities (IDD) are in need of effective physical fitness training programs, leisure time opportunities, and strategies to improve their participation in daily life activities. Purpose. This study sought to present an educational program that enabled the implementation of a virtual reality (VR) program operated by in-house caregivers for adults at a severe level of IDD. Methods. During the initial stages of this series of studies, 2 groups of participants underwent a video-capture, VR-based, game-like, exercise program. The first study group (N = 33; mean age = 28.1 ± 5.3 years; moderate IDD) was trained by an experienced occupational therapist, and the second study group (N = 30; mean age = 52.3 ± 5.8 years; moderate IDD) was trained by occupational therapy students. Changes in physical fitness were monitored for all participants in comparison to matched control groups. A third study group (N = 20; mean age = 48.1 ± 8.6 years; severe IDD) was trained by in-house caregiver staff. An educational program including gathering appropriate caregivers, presenting theoretical background for the program, as well as providing on going technical support was implemented. Results. The strategy used to enable the implementation of a VR program by inhouse caregivers was shown to be feasible. The VR intervention program promoted activity and was motivating to and enjoyable by all participants with mild to moderate IDD and to most individuals with severe IDD. Significant (P Conclusion. VR technology was found as fully effective tool to engage adults with mild to moderate IDD, and some with severe levels of IDD, in a variety of activities by caregivers from different educational backgrounds and professions. Key Words: Intellectual disability, Developmental disability, Virtual reality, Physical fitness, Best practices. BACKGROUND AND PURPOSE The fact that many individuals with intellectual and developmental disability (IDD) maintain a sedentary life style, experience poorer health and have less access to health care than the general population,1 suggest that these individuals are at risk for a multitude of secondary health problems. However, the physical condition of this population may improve with appropriate intervention.2 Previous studies reveal that provision of additional leisure opportunities and participation in leisure activities by individuals with cognitive limitations contributes to improvement in self-confidence and self-concept, improvement in social and motor skills, increased communication abilities, greater physical fitness and weight reduction.3-5 Although participation in vigorous leisure activities has been shown to improve participants' physical fitness, coping skills, level of stress, and adjustment to a life with disabilities, the majority of leisure pastimes available for people with severe cognitive and physical limitations is often extremely limited, tending to involve sedentary activities.6,7 A review of the literature on leisure activities for people with disabilities highlights the need for increased exposure to augmented leisure opportunities and documents a positive relationship between satisfaction with leisure and self-esteem, companionship, enjoyment and relaxation.8 At the same time, the pervasive lack of opportunities for a wide choice of independent leisure activities may contribute to the development of dependent behavioral patterns, learned helplessness and depression.8-11 For individuals with IDD, some limitations initially must be overcome to take part in demanding physical activities. These limitations include: * Physical environment: Adults living in nursing homes were less likely to exercise than the non-nursing home residents12; therefore, in order to enhance participation, activity programs must be made available for this population. …