This research paper explores the factors that determine the variation in intervention decisions of regional powers in civil conflicts within their region. The research argues that a regional power's intervention decision is influenced by a range of strategic interests shaped by domestic, regional, and global factors. Using the case study of India and China's role in the Maoist insurgency in Nepal, the study identifies and develops four conditions under which regional powers are less likely to intervene: internal constraints, willingness, regional security concerns, and regional and global power dynamics. These conditions determine whether a regional power adopts a non-interventionist, strategic limited interventionist, or full-interventionist policy. Existing literature tends to focus on a binary approach to intervention/non-intervention, assuming that regional powers will intervene based on their capabilities and interests. However, such studies do not account for the observed empirical variation in intervention. This research aims to fill this gap in the literature by exploring why this happens and what factors cause the variation in intervention by regional powers.