Foundations for OT Cybersecurity: Asset Inventory Guidance for Owners and Operators

Operational technology (OT) systems form the backbone of critical infrastructure, yet their complexity and connectivity make them prime targets for cyber threats. This guidance from CISA and global partners stresses the importance of building and maintaining a detailed OT asset inventory paired with an OT taxonomy. Together, these tools help owners and operators classify assets by function and criticality, strengthen defenses, and improve response to vulnerabilities. Real-world examples from the energy and water sectors highlight how structured inventories can reduce risks, support resilience, and safeguard essential services.