Pricing general road usage using vehicle borne electronics

In developing a system to charge for road usage, especially in cities, the author considers a complex pattern of existing use and freedom of travel which the roaduser currently enjoys. To make any system of charging politically acceptable it must be seen to be reasonable by both those who would pay and those who decide to impose it. The article considers the subject of charging for motorway use as a simpler issue in all respects than one concerning urban charging, so thinking has concentrated on urban issues rather than inter-urban ones