Decision-making glossary
Decision journal
A decision journal is a personal record in which you write down a decision before you know how it turns out: the situation, the options, what you expect to happen, and how confident you are. Reviewing it later shows where your judgment was good and where you were simply lucky, which memory alone cannot do.
The point of a decision journal is to catch your reasoning before hindsight edits it. Once an outcome is known, people tend to remember having expected it. A dated entry written at the time is the only reliable evidence of what you actually thought.
A useful entry is short: the context, the options considered, the expected outcome with a probability, and a date to check back. Some versions also note your state at the time, such as tired or rushed, because it affects judgment. Farnam Street’s template includes these fields and a few more.
A decision journal is usually individual, and a decision log usually shared. The mistakes are the same for both: writing entries after the fact, recording the choice but not the expectation, and never scheduling the review, which is where the learning happens.
In Decize: Decize applies the same discipline to a team: confidence and an optional forecast are recorded when the decision is made, and recording the outcome triggers a short comparison of what was predicted against what happened. See how →
Free template: Decision journal template