The past, present, and future of supply chain concentration: Emerging developments and future directions

Supply chain concentration (SCC) has emerged as a critical feature of modern supply networks, shaping firm risk exposure, power dynamics, and performance outcomes. Despite growing scholarly attention, existing research remains fragmented in its conceptualization, methodological approaches, and interpretation of outcomes. To address these limitations, this study employs a systematic literature review and content analysis of peer-reviewed articles retrieved from the Scopus database. Following a multi-stage screening process based on relevance, quality (CABS and ABDC rankings), a final sample of 75 studies was analyzed to identify key constructs, methodological patterns, and outcome relationships within the SCC domain. The findings reveal that SCC is a multidimensional construct encompassing structural, relational, and cognitive dimensions, with effects on financial performance, sustainability, innovation, and resilience. We also uncover significant methodological concentration around regression-based techniques, limiting the field’s ability to capture complex, multi-level relationships. This study is original in three key ways. First, it provides one of the most comprehensive and integrative syntheses of SCC research by simultaneously examining predictors, outcomes, moderators, mechanisms, theories, and contexts within a unified framework. Second, it advances theory by repositioning SCC as a dynamic strategic condition rather than a static structural dependency. Third, it develops a forward-looking research agenda that introduces underexplored dimensions such as digital interdependence, managerial cognition, and institutional variability. Overall, this study offers a consolidated framework and research roadmap that enhances conceptual clarity, strengthens methodological rigor, and guides future research toward a more holistic understanding of supply chain concentration in increasingly complex and globalized environments.