All limit design theories are based on the principals of equilibrium of forces and compatibility of deformations at the state of impending collapse. Use of these theories is dependent on an ability to predict the moment rotation relationships of structural members. An investigation was carried out to improve on the accuracy of methods for predicting moment-rotation relationships of reinforced concrete beams. Tests on 40 beams are reported. In addition, the results of these tests and of tests previously reported on 37 beams are analyzed. The variables considered include size, beam width, reinforcement index, and binding by closed stirrups. A method is proposed for the computation of the rotational capacity of hinging regions in reinforced concrete beams.