Thinking books · Decision making · Gary Klein, 1998

Sources of Power — the big ideas

How experienced people actually decide under time pressure, studied in firefighters, nurses and soldiers.

Free — no account needed to read

The big ideas

Experts usually do not compare options. They recognise the situation as a type, retrieve one plausible course of action, mentally simulate it, and run it if it works — comparison happens only when simulation fails.

Expertise is largely perceptual: noticing the cue that this situation is not what it appears. That is trained by exposure and feedback, not by decision theory.

The premortem — imagining the failure has happened and explaining it — makes doubts sayable that hierarchy and optimism otherwise suppress.

It is a useful corrective to the bias literature: under real conditions, intuition built on genuine feedback is often the better instrument.

Practise it — no need to have read it

Take a plan you are committed to. Assume it has failed completely. Write the story of how, specifically, and in sequence.

A hint: Then for each cause, decide: prevent, detect early, or accept.

Where it shows up in real life

• Project planning
• Operational decisions
• Knowing when to trust your gut and when not to

Described in our own words with the source named — never quoted, and not a substitute for reading the book.