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This WRC Bulletin presents a simplified method for the evaluation of creep-fatigue damage based on the responses of materials to cyclic and steady loading histories. The method captures the damage mechanisms of research tests for combined creep and fatigue loadings. Its recommendation to use cyclic properties for transients permits a higher elastic strain range in a thermomechanical cycle without excessive creep damage. Additional data requirements for the analyses can be acquired in the design phase or approximated from current and past research. The method has been successfully used in the design of components for ultra-high temperatures. Publication of this document- WRC Bulletin No. 394 was sponsored by the Committee on Elevated Temperature Design of the Pressure Vessel Research Council