This section turns to literature and experts' discussions to explore these questions. The problem of the term's conceptual ambiguity in European policy making was identified during research for the COST Action "Accessibility instruments for planning practice in Europe" (Silva and Larsson, 2018). Silva and Larsson explain that "accessibility" is often used without definition or given a connotation that is quite different from the term's meaning in a transport context: the ease of reaching destinations or activities distributed in space.