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Resilience Engineering Guide

Resilience engineering studies how people, teams, and organisations succeed under everyday pressure — not only how they fail. Rather than treating safety as the absence of accidents, it asks how systems adjust, learn, and anticipate so that required work keeps going when conditions change. This guide introduces the main ideas developed on this website and points to deeper pages for each theme.

From Safety-I to Safety-II

Safety-I defines safety by counting things that go wrong. Safety-II defines safety as the ability to succeed under varying conditions — understanding everyday performance is a prerequisite for understanding safety performance. Read more in Safety-I and Safety-II (2014) and the book Safety-I & Safety-II.

Resilient performance

Resilience is not merely recovery after breakdown. Resilient performance is the ability to adjust functioning before, during, or after disturbances so that required operations continue under both expected and unexpected conditions. The concept was developed with David Woods and colleagues; see Resilience engineering (2004) and related volumes listed under Books.

The ETTO principle

Efficiency-Thoroughness Trade-Off (ETTO) explains why people and organisations routinely balance getting things done quickly against checking them carefully. The same trade-off shapes both success and failure. Explore The ETTO Principle (2009).

FRAM — Functional Resonance Analysis Method

FRAM models how functions depend on one another and how variability can combine in unexpected ways. Its purpose is to describe how something happened, not to hunt for a single root cause. See FRAM (2012) and the book Functional Resonance Analysis Method.

Where to go next

Browse the full chronology of ideas on the Ideas page, publications in Papers etc., or the complete bibliography under Books. For biography and contact, see the CV section.