Abstract
A brief history is presented of the analysis of the economy of highway improvements. The following basic input information needs are discussed: traffic performance, motor vehicle running cost, cost of traffic accidents, system data, the value of travel time and relationship of road user consequences to non-use consequences. The state of highway economic analysis is summarized from two standpoints: (1). The need for added meaningful data to fill the gaps in existing knowledge and (2). The need for more advanced approaches to analysis.