Resilience engineering is the practice of designing systems to keep functioning during disruption, recover quickly, and reduce the impact of failure. In cyber security, it goes beyond prevention: it assumes breaches, outages, and sabotage can happen, and builds for continuity, safe fallback modes, rapid restoration, and clear recovery procedures.
This matters because many attacks succeed by forcing an organization to lose availability, not just by stealing data. Ransomware, destructive malware, DDoS campaigns, and attacks on critical infrastructure can interrupt service even when an intrusion is detected early. Resilient systems use segmentation, redundancy, backups, monitoring, incident playbooks, and tested recovery paths to limit damage. Defenders apply resilience engineering to keep essential services running while investigating and containing the threat.