Accessibility, usability and universal design—positioning and definition of concepts describing person-environment relationships

Literature review, synthesized with the authors' research and practice experiences.

The authors suggest an instrumental, three-step definition to accessibility, highlighting that accessibility comprises a personal as well as a environmental component, and that accessibility must be analysed by an integration of both. Suggesting the introduction of an activity component, accessibility should partly be replaced by the more complex term usability. Universal design is highlighted as a more process-oriented but less stigmatizing concept.