In most countries, projects are chosen and defined on the basis of a cost-benefit or cost-advantage analysis, with public hearings being used to aid in this definition process. Cost-benefit analysis has long included both congestion and accident effects: the value placed on time and on life are already old concepts.
Although this type of analysis has been done comprehensively and stringently for projects in rural areas, it is done less frequently in urban areas, even though it is here than congestion is highest.