Orientation and mobility research: What is known and what needs to be known

This article provides an overview of research about orientation and mobility (O&M) of persons with blindness or severe visual impairment. It reviews the development of measures that assess mobility and discusses the use of these measures in the study of factors that influence travel in “natural” travel environments. It then traces the development of measures related to spatial orientation and provides a review of orientation research. The final section describes several important areas for future research in O&M.