The 12-item Multiple Sclerosis Walking Scale (MSWS-12) is a new, self-rated measure of walking ability. The scale has not been independently validated for use in differing MS populations. One hundred forty-nine patients in the community and 53 hospital outpatients with MS completed the MSWS-12 and other outcome measures. The psychometric properties of the MSWS-12 were excellent, and in particular the scale is responsive to change.