The relationship between physical functioning and physical activity is a reciprocal one; physical functioning provides the individual with the capability to engage in physical activities, and physical activity helps to maintain and in some cases improve physical functioning. This reciprocal relationship, coupled with the high prevalence of physical inactivity among persons aging with a disability, has profound implications for rehabilitation practice, especially in evaluating intermediate and long-term outcomes of clinical practice. For rehabilitation to play a role in the long-term maintenance and enhancement of physical functioning among persons with disabilities, increasing participation in various types of physical activity in the community must be part of the recovery and maintenance continuum [12,22]. There is also a critical need to identify specific doses of physical activity for specific disabilities and secondary conditions. HMOs and other health insurers will require evidence-based outcomes before establishing reimbursement procedures for physical activity programs for persons aging with a physical disability.