One complete session of the American Concrete Institute 54th annual convention in Chicago was devoted to previewing highways of the future based on present design requirements, construction practices, and experimental work now going on with concrete pavements. In view of the expanded highway program now in progress, it was emphasized that highway engineers should be thinking of present design requirements for concrete pavement in terms of 1980, the latest target date for completion of the interstate system. It is quite likely that some of the experimental work now in progress will form the basis for the pavements of tomorrow. At the present time, 1958, permissible axle loads for commercial vehicles range from 18,000 to 22,400 pounds. The tendency to increase axle loads in certain areas will continue. Permits for operation of heavy haulers equipment are increasing rapidly each year; axle loads as high as 35,000 pounds on multiple wheel axles are becoming common. The frequency of axle load applications, a major factor in pavement design, is increasing in proportion to increase in traffic and travel trends. Between 1950 and 1956 there was approximately a 7 percent per year increase in ton-miles carried by commercial vehicles. This continuing trend could represent an imposing load to be carried by the pavements of 1980. All of these load factors must be considered in selecting design wheel loads in building today's pavements for tomorrow's use. Although a few experimental prestressed concrete pavements have been built in the United States, the countries in which the largest share of investigative work in the form of field slabs and tests have been undertaken in England and France. Such investigations have proved that it is possible to augment sufficiently the strength of concrete in tension by inducing an initial compressive stress that a pavement slab so constructed will have a load bearing capacity many times that of a conventional concrete slab of the same thickness on the same subgrade. Other experimental slabs include continuous reinforcing and concrete overlays.