Project aims are a) to test the efficacy of a physical exercise program for adults with Down syndrome and b) to test the applicability of the transtheoretical model and social cognitive theory for predicting long- term adherence to enhanced physical activity in this population. It will also test the effects of a health promotion program on their physiological, adaptive behavior, and psychosocial outcomes. The design includes three randomized groups (n=36 per group): control and two intervention groups. Both intervention groups will received a 12-week center-based group exercise and education program offered at the Institute on Disability and Human Development's Center on Health Promotions for Persons with Disabilities. Only one of the intervention groups will receive the caregiver education programs. The project objectives are the following: 1. Test the efficacy of the exercise and education program for older adults with Down syndrome immediately following the program and in four six month intervals after the program is completed. The Exercise program is geared to increase cardiorespiratory fitness, muscle strength, and endurance. The education program for the adults with Down syndrome aims to increase knowledge of exercise benefits and to increase perceived exercise self-efficacy. 2. Assess the long-term benefits of a caregiver (family or vocational and residential staff) education training program geared to help caregivers support adherence to an exercise program. Outcomes assessed to four six month intervals following the program includes exercise adherence, physiological functioning, adaptive functioning, and psychosocial functions of the adult with Down syndrome. 3. Determine predictor variables associated with exercise adherence in the short and longer term (immediately after the training and in four six month intervals after the training)> Predictor variables include level of disability, age, type of residence, and exercise decisional balance (balance of perceived gains and losses and exercise self-efficacy of the adult with Down syndrome.