Supply chain mapping extends beyond direct suppliers (tier 1) to include sub-suppliers, logistics providers, and dependencies multiple tiers deep, creating visibility into hidden vulnerabilities. This reveals concentration risks, geographic exposures, single points of failure, and compliance risks in opaque portions of the supply network. When semiconductor shortages emerged in 2021, companies with comprehensive supply chain maps could identify exposures faster and develop mitigation strategies. Effective mapping uses technology platforms to maintain dynamic network views, incorporates risk indicators for each node, and enables scenario analysis of disruption impacts across the extended supply ecosystem.