This article discusses the relationship between demographics, energy, and transportation, recognizing that demographic changes and energy constraints will place pressures on the transportation system that must be addressed by policy. The major demographic trends include declining household size and moderate population growth. Also, the labor force will increase more rapidly than the population. Both jobs and households will increasingly be located in the suburbs, where the dominant transportation problem in the next two decades will be. Occasional energy shortages and steadily increasing gasoline prices will exacerbate the suburban travel problem, but chronic gasoline shortages should not be a problem in this century. Transportation policy themes will focus on better use and management of existing resources.