Why is Accessibility Metadata Proving Difficult?

Accessibility metadata is simply metadata that describes the accessibility of resources and services, usually those on, or available through, the web. Awareness of widespread web content inaccessibility led to work being done to develop guidelines for authors and others to make sure that content would be more accessible to those with special access needs, especially those with disabilities who were being disen-franchised by their lack of access to the web. Currently, work is being done to find ways of signalling the degree of accessibility of resources, and ways of matching resources to searches and people. In addition, accessibility metadata could be used to repair some inaccessi-bility problems on the fly. This paper describes some of the work being done and the problems that have contributed to make the progress comparatively slow.