This paper is an endeavor to quantify the concept of sustainable transportation. The prevailing idea in the context of sustainable development (SD) emphasizes on the reduction of transportation demand in order to reduce the environmental and social consequences of it. Nevertheless, in the current paper using a measure for SD, and based on the conformity of the growths of all sectors with transportation supply and demand, the countries are comparatively studied. The measure, elasticity, for each two variables indicates the extent to which those two variables have been changing consistently. Indeed the elasticity values are measures of a “harmonic development” representing sustainability. The database consisted of national variables in transportation, economic, social and environmental categories for 128 countries in the period of 1980 to 1995. The study shed some light on the SD of transportation supply and demand, reflecting the harmony of social, environmental and economic development with respect to transportation supply and demand development. Using individual elasticity, composite sustainability indices were suggested. For comparative appraisal, country groupings were developed. The sustainability appraisal showed interesting patterns of within and between group similarities and differences. The study confirmed the significance of transportation supply and demand balancing and sustainability challenges of the 21st century. The methodology may be applied to any other time and geographic scope for addressing pertinent issues for balancing and SD of transportation systems.