A useful A3 problem statement tells the reader what is happening, where it is happening, and how the result differs from the expected performance. It gives the investigation a specific starting point without deciding the cause in advance.
Lean Enterprise Institute describes a good problem statement in terms of an observable, measurable difference between actual performance and the target or standard. Lean Enterprise Institute: Why Effective Problem Solving Begins With a Good Problem Statement
Use the steps below to turn a broad concern into a short statement supported by evidence.
1. Name the process and the observed problem
Every example, number, standard, and date below is fictional and provided for learning. These are not customer results or recommended benchmarks.
Suppose an internal purchasing team says:
“We keep having problems with purchase requests.”
That statement leaves several questions open. Are requests late, incomplete, duplicated, or rejected for another reason? Which requests are included?
For this example, define the scope as purchase requests received by the central purchasing team during October. Define the observed problem as a request returned to its submitter because the required cost-center field is blank.
This definition describes a visible condition. It does not explain why the field was left blank.
2. Establish the actual performance
Review the relevant records and document the counting rule before calculating a rate.
The fictional team's October review finds:
- Requests received: 400.
- Requests returned for a blank cost-center field: 48.
- Counting rule: Count each affected request once, even if it is returned more than once.
- Recorded follow-up time: 18 staff hours spent obtaining the missing information for those requests.
The affected-request rate is 48 ÷ 400 × 100 = 12%.
Keep the reporting period, source, and counting rule with the A3's supporting data. “48 returns” alone could mean 48 unique requests or repeated returns involving fewer requests. That ambiguity could change the baseline.
3. Compare actual performance with the standard
In this example, the team's documented process standard is that no more than 3% of received requests should require a return for a blank cost-center field.
| Measure | Actual October result | Existing standard | Performance gap |
|---|---|---|---|
| Requests returned for a blank cost-center field | 12% | No more than 3% | 9 percentage points above the limit |
At October's volume of 400 requests, 3% corresponds to 12 affected requests. The actual count of 48 is 36 above that level.
Write nine percentage points, rather than “nine percent,” for the difference between 12% and 3%.
If your team has no agreed standard, say so. Establish the expectation with the responsible people and explain its basis. Do not invent an industry benchmark to make the A3 look complete.
4. Write the problem statement
Bring the scope, actual result, standard, and supported impact into a short paragraph:
During October, 48 of 400 purchase requests received by the central purchasing team were returned for a blank required cost-center field. The 12% affected-request rate exceeded the team's 3% limit by nine percentage points. Records show 18 staff hours spent obtaining the missing information for those requests.
This statement gives the team a defined set of cases to investigate. It does not claim that training, workload, software, or carelessness caused the missing information.
ASQ separates the problem and current-condition sections of an A3 from cause analysis and subsequent countermeasures. Keeping that distinction helps avoid presenting an explanation as an established fact. ASQ: A3 Report
5. Keep the improvement target clear
The problem statement describes the current gap. The improvement target states the result the team intends to reach and when it will assess it.
For this fictional exercise, the proposed target is:
By December 15, reduce the proportion of requests returned for a blank cost-center field to 3% or less, measured across all requests received during the four weeks ending on that date. Use the same counting rule as the October baseline.
Confirm that the proposed target, timing, and measurement period are appropriate before adopting them in a real project. Here, the dates illustrate how to make a target testable; they do not predict how long improvement will take.
The target also leaves the method open. “Install a mandatory form field” would be a proposed countermeasure to evaluate, rather than the performance result itself.
ASQ advises connecting an improvement target to the current state and the problem being addressed. ASQ: A3 Report
Weak and stronger A3 problem statements
Too broad
Weak: “Purchasing is inefficient.”
Stronger: “In October, 12% of purchase requests received by the central purchasing team were returned for a blank required cost-center field, compared with a 3% limit.”
The revision identifies a process, period, observable condition, and measurable gap.
An unverified cause
Weak: “Untrained employees are causing incomplete purchase requests.”
Stronger: “Forty-eight of 400 October requests were returned for a blank required cost-center field.”
The revision removes an unsupported explanation. Whether training contributed remains a question for investigation. Add the standard and documented impact when building the full statement.
A solution written as the problem
Weak: “We need a new purchasing system.”
Stronger: “The October return rate for blank cost-center fields was 12%, against a limit of 3%.”
The revision states what needs to improve. It leaves the team free to investigate the workflow and compare possible changes.
Check the statement with the people doing the work
Before moving into cause analysis, ask:
- Can another person identify the same affected requests using the definition?
- Do the numerator and denominator cover the same period and population?
- Is the comparison standard documented or clearly marked as proposed?
- Is each impact claim supported by records or observation?
- Have guesses about causes been kept separate from the facts?
A3 thinking includes discussion and investigation, rather than simply completing a form. Lean Enterprise Institute describes the A3 as a process for examining the situation, considering countermeasures, assigning action, and checking evidence of results. Lean Enterprise Institute: A3 Report
Put the statement into an A3 worksheet
Keep the final statement short and place the detailed counts, definitions, and supporting evidence nearby. Update it if further investigation shows that the original scope or baseline was wrong.
The $12 Lean Tools Practice Pack includes a printable A3 worksheet and a companion fictional worked example. Use it to record the problem, evidence, proposed action, and follow-up as your investigation develops.