Measuring accessibility provides the ability to extend the methodology to other areas of study, eg assessing the vulnerability to issues such as resource dependency. Measuring the dependence on ‘oil’ for the private motor vehicle for a nation, region or city/town would be a fairly simple extension of the accessibility score methodology. This would enable the quantification of a particular area’s potential minimum energy use to be determined (reflecting what people ‘could’ use) and then compared against actual energy use (what people ‘would’ use). The indicator may result in a ‘resource vulnerability footprint’ that would enable comparison between areas and help direct policy. A methodology similar to that proposed by Abley et al (2011) could be appropriate.