Investigation of intergral bent cop in straight, continuous, reinforced concrete box-girder bridges indicate that reductions in the amount of flexural reinforcement in the bent cap of up to 40 percent can be made without reducing safety and while maintaining adequate serviceability. Even greater reductions in the amount of reinforcement can be made for bent caps with flared columns. Most of this improved economy results from a change from working stress to the load factor method of design. Many variables (load distribution, effect of flaring the column, effective flange width, effect of spreading the main tensile reinforcement, and the location of the critical deisgn sections) were studied. The experimental program included tests on scale models, and the analytical studies included development of a computer program.