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This Bulletin contains two reports that compare the French RCC-M Pressure Vessel Code and the U.S. ASME Section III Code on Design of Nuclear Components and Piping Design Rules. Publication of this report - WRC Bulletin No. 361 was sponsored by the Pressure Vessel Research Council of the Welding Research Council. This paper presents the studies made for preparing the evolution of the French RCC-M Pressure Vessel Code dealing with Fatigue analysis methods. Fatigue analyses shall use strain corrections applied to elastic analyses when plasticity occurs. These corrections may concern: Poisson's ratio variation when plasticity occurs, elastic follow-up effects, strain concentrations in minor discontinuities. In many cases, these various effects may act simultaneously, leading to a need for a global logical approach including the contribution of all of them. The aim of the paper is to present such an approach, and to give the results of its application in representative geometrical configurations subjected to realistic combined loadings including pressure, external loads and thermal effects.