Working familiarity with service/dependency mapping concepts and at least one mapping tool (ServiceNow Service Mapping, BMC Helix, etc.) - enough to ask the right validation questions of a technical lead, even if not personally building maps. Assess whether service maps currently in progress or "complete" are being validated by someone with the technical authority to confirm accuracy - a stale or unvalidated service map is a silent risk that won't show up in a status report until an incident exposes it.