The purpose of this three phase study is to evaluate a Pushrim Activated Power Assist Wheelchair (PAPAW). Phase I will examine whether the steady-state, metabolic energy efficiency for propelling a manual wheelchair with and without the device will be significantly different. In Phase II, wheelchair users will evaluate the PAPAW over activities of daily living course to determine its usability and acceptability and to identify areas for future development. Finally, in phase III, comparison of activities of daily living in the community will be made between the subjects when using their personal wheelchair and a PAPAW.