CISA, along with the National Security Agency, the Federal Bureau of Investigation, Environmental Protection Agency, and several international partners, released comprehensive guidance to help operational technology (OT) owners and operators across all critical infrastructure sectors create and maintain OT asset inventories and supplemental taxonomies. 

An asset inventory is a regularly updated, structured list of an organization’s systems, hardware, and software. It includes a categorization system—a taxonomy—that classifies assets based on their importance and function. This guidance explains how OT owners and operators can create, maintain, and use asset inventories and taxonomies to identify and safeguard their critical assets. 

Following this guidance, organizations may gain deeper insights into their architecture, optimize their defenses, better assess and reduce cybersecurity risk in their environments, and enhance incident response planning to ensure service continuity.