There has been renewed interest among local and state agencies in tolling as a workable revenue-generating option for financing highway construction and maintenance activities. A multitude of complex decisions face the toll facility operators and researchers. An operational typology of tolling concepts for highway financing is presented and a framework for the analysis of such concepts and for the examination of related policy issues in a systematic manner is provided. Documentation is provided that characterizes existing toll operators in the United States. This is accomplished through a survey of operators, the results of which are analyzed according to the dimensions and levels of the foregoing typology. Finally, cell inconsistencies are examined, and cells that correspond to existing tolling concepts are highlighted. The typology also helps to identify tolling approaches that many not currently be in use but may nevertheless be worthy of further consideration.