The full-depth control joint is basically a combination expansion-contraction joint between one-fourth and one-half inch in thickness and having a depth equal to the full depth of the slab into which it is built. It incorporates standard load-transfer devices and makes use of non-extruding resilient fillers and hot-poured sealers. Among the advantages claimed for the full-depth control joint is the elimination of the costly operation of sawing joints, along with the attendant problems of timing; the reduction of curing cracks to a minimum level and the control or elimination of such additional trouble sources as the following: random or unwanted cracking between joints; plane-of-weakness contraction joints and the haphazard cracking that accompanies the formation of such joints; and the creation of joints which are either too wide to retain an adequate seal or too narrow to be sealed and maintained as joints. The Concrete Joint Institute's specific proposal is that comparative test projects be constructed consisting of a moderate length section of divided interstate highway (two separate roadways) lying between two structures. One-half of each roadway would be built in accordance with the standard interstate design currently in effect in the state in which the study was being made. The other half of each roadway would be identical in all respects, including joint spacing and load transfer devices, except that all contraction and expansion joints would be replaced by full-depth control joints one-fourth to one-half inch thick. Comparative data would be accumulated on construction and maintenance costs, performance , and projected length of service for the two pavements.