Purpose The design of multi-tier supply chain networks is a central but underexplored matter in the literature. How firms determine the optimal number of supplier tiers can impact their resilience and visibility. This study addresses this gap by considering the concept of reachability of the focal firm. It examines how network structure, based on centrality metrics, affects firm performance and resilience. Design/methodology/approach The study uses a two-phase, mixed methods design. In study 1, a reachability analysis of the US pharmaceutical supply network helped determine the optimal number of upstream tiers given random disruption scenarios. This analysis identifies a convergence tier, a point after which added visibility has diminishing returns. In study 2, the impact of focal firm's position in the network on firm performance is investigated. This study uses degree and betweenness centrality as structural indicators to test the relationship between financial performance and financial resilience using econometric methods. Findings The findings from Study 1 show that reachability decreases non-linearly as the number of tiers increases. This indicates that there is a finite and quantifiable range of visibility that maximizes the focal firm access (reachability) to the suppliers under random disruptions. In Study 2, it was found that betweenness centrality, which reflects brokerage positions within the network, significantly enhances financial performance. Additionally, degree centrality, which indicates the number of direct supplier connections, has a positive impact on financial resilience. Originality/value This study presents a data-driven approach to determine the optimal monitoring depth in complex supply networks, linking it to firm-level financial outcomes. By combining reachability analysis and centrality metrics, it connects network design with organizational resilience. This work offers a quantitative framework to help firms build resilient, disruption-ready supply networks.
Parast et al. (Sat,) studied this question.