Apart from its clear academic relevance,the study on the stability of fully developed concentric core-annular flow in straight circular pipes is motivated by its technologicalimportance with applications such as in the prediction of two-phase flow pattern transitions. This paper presents a detailed review on the progress of the linear stability analysis of its flow configuration. The discussion centres on the relationship between the instability mechanism and the two-phase flow pattern transitions. Some important topics in connection with the simulated microgravity experiments on two-phase flow patterns in the territorial normal gravity environment are also pointed out for the future research.