Abstract
The concepts of demand schedules for urban vehicle trips and supply schedules for road networks are presented as a framework for the examination of usage, operating costs and levels of service with various network modifications over a period of time. The model enables the interaction between public transport, private transport, the road network, personal preferences and returns (or subsidies) to public transport to be visualized, and thus provides a basic framework for the analysis of an urban transportation network rather than a highway network.