Design for fatigue failure is usually the most critical aspect in the design of engineering components. It is essential to be able to predict the fatigue load of components in operation. Most of the methods for predicting fatigue life currently are based on empirical approaches. The results of controlled experiments of specimens subjected to fatigue loading are plotted on (S-N or ε-N) graphs, and the applied load is used to determine the number of cycles to fatigue using these graphs. An important aspect that is not taken into consideration is the significant variation in fatigue life at a given stress or strain amplitude. The origin of this scatter is not well understood. One possibility for the scatter in fatigue life might be due to the wide range of defects distributed over the volume, which leads to materials behaving at a micro-scale from homogeneity to heterogeneity. In other words, microscale heterogeneities may play a significant role in the observed scatter in fatigue life. There have been few approaches which have modelled the presence of such microscale heterogeneities in terms of mechanical behavior and their effect on the scatter in the observed fatigue life. In this work, we study a multi-spring model as earlier presented by Masing in 1924. This model is based on describing the mechanical response of the material in terms of a number of parallel elastic-perfectly plastic springs. Earlier studies on this Masing model have considered variations in the yield strength of the individual spring components. This model was shown to present some of the aspects of fatigue life behavior of materials. In this work, we propose to study modifications and extensions of the Masing model. Variations in the stiffness of the springs, the yield strength, and the failure strain are all considered to observe the effect on the predicted fatigue life.