What is resilience?

The short answer is that resilience is the intrinsic ability of a system to adjust its functioning, prior to or following changes and disturbances, so that it can sustain operations even after a major mishap or in the presence of continuous stress.

A resilient system, where a system can be anything from an individual to a global socio-technical organisation, must have the following three abilities:

• The ability to respond, quickly and efficiently, to regular disturbances and threats.
• The ability continuously to monitor for irregular disturbances and threats, and to revise the basis for the monitoring when needed.
• The ability to anticipate future changes in the environment that may affect the system’s ability to function, and the willingness to prepare against these changes even if the outcome is uncertain.

Resilience engineering provides the methods by which a system’s resilience can be gauged or measured, and the means by which a system’s resilience can be improved.