ISO 9001 Clause 10, Improvement, closes the loop: find and act on improvement opportunities (10.1), correct nonconformities and eliminate their causes through corrective action (10.2), and continually improve the suitability and effectiveness of the QMS (10.3).
Clause 10 is the "Act" in Plan-Do-Check-Act. Everything the system measured in Clause 9, audits, customer feedback, process data, lands here as a decision: fix it, prevent it from coming back, and make the whole system a little better. It is a short clause, but it is where a quality system either earns its keep or reveals itself as a filing exercise. A plant that closes the same nonconformity every quarter has a Clause 10 problem, not a bad-luck problem.
What does ISO 9001 Clause 10 require?
Clause 10 has three sub-clauses. 10.1, general, sets the expectation that you determine and select opportunities for improvement and act on them to meet requirements and enhance customer satisfaction. 10.2, nonconformity and corrective action, is the detailed engine: when something goes wrong, react, contain, find the cause, remove it, and check the fix. 10.3, continual improvement, requires that you keep improving the suitability, adequacy, and effectiveness of the QMS over time. Together they make sure the system does not just run, it gets better.
One thing worth flagging up front: ISO 9001:2015 removed the separate "preventive action" clause that older versions had. Its intent did not disappear; it moved into the risk-based thinking of Clause 6.1. So Clause 10 is now about reacting and improving, while preventing problems before they occur lives in planning. Knowing that split saves a lot of confusion at audit.
What does 10.1 general improvement require?
Clause 10.1 is the short, framing sub-clause. It requires the organization to determine and select opportunities for improvement and implement the necessary actions to meet customer requirements and enhance customer satisfaction. It names three kinds of improvement: improving products and services to meet requirements and address future needs; correcting, preventing, or reducing undesired effects; and improving the performance and effectiveness of the QMS itself.
In practice 10.1 is the license and the expectation for everything from a small kaizen on a changeover to a capital project that eliminates a chronic defect. It tells you improvement is not optional or purely reactive; you are expected to go looking for it. The best sources of opportunities are the outputs of Clause 9: audit findings, customer feedback, data analysis, and management review.
How does 10.2 nonconformity and corrective action work?
Clause 10.2 is the detailed heart of Clause 10, and it reads almost like a checklist. When a nonconformity occurs, including one arising from a complaint, the standard requires you to react to it (control and correct it, and deal with the consequences), then evaluate whether action is needed to eliminate the cause so it does not recur or occur elsewhere. If it is, you find the cause, implement action, review whether that action was effective, update risks and opportunities if needed, and change the QMS if needed. Then you keep records of the nonconformities, the actions taken, and the results.
That is the same discipline as a full corrective and preventive action (CAPA) process, and the two map directly onto each other. The single most important word in 10.2 is "cause." The clause explicitly asks you to review and analyze the nonconformity, determine its causes, and determine whether similar nonconformities exist or could occur. Stopping at "the operator made a mistake" fails that test, because operator error is a symptom, not a cause. Structured tools, root cause analysis methods, the 8D problem-solving discipline for serious or customer-facing issues, are how you satisfy the cause requirement with evidence instead of a guess.
What is continual improvement (10.3)?
Clause 10.3 requires you to continually improve the suitability, adequacy, and effectiveness of the QMS, using the outputs of analysis and evaluation and of management review to identify where improvement is needed. It is deliberately open-ended. There is no target number of improvements per year; the requirement is that the system demonstrably gets better over time and that you use your own data to steer it.
The practical read: continual improvement is proven by a trail. Objectives that tighten as they are met, corrective actions that reduce a defect category quarter over quarter, a management review that consistently turns data into decisions, an improvement program like kaizen that runs whether or not an audit is coming. A plant with flat performance and a folder of closed-and-forgotten corrective actions is not continually improving, no matter what the procedure says.
A useful way to picture 10.3 is a ratchet. Each corrective action and each improvement locks in a slightly better baseline that the plant does not slide back below. The mechanism that stops backsliding is standardization: when a fix is captured in the work instruction, built into the fixture, or added to the training, the improvement survives the next shift change and the next new hire. Without that step, gains leak away and the same defect returns a quarter later, which is the difference between a plant that is busy and a plant that is improving. Auditors read this in the trend lines, not the meeting minutes.
How does Clause 10 connect to CAPA and the plant's kaizen program?
Clause 10 is the standard's language for two things the plant floor already does under other names: corrective action and continuous improvement. 10.2 is CAPA, formalized; it is the same react-contain-find cause-fix-verify loop, and your CAPA process is the evidence that satisfies it. 10.3 is the umbrella over your improvement program, whether you call it kaizen, lean, or continuous improvement.
The link between them is important. Corrective action (10.2) is reactive, triggered by something that went wrong. Continual improvement (10.3) is proactive, going after opportunities before a nonconformity forces the issue. A healthy quality system uses both: 10.2 to make sure problems get fixed once and stay fixed, 10.3 to raise the baseline so fewer problems occur at all. When you run them together, the corrective actions from 10.2 become a data source for 10.3, the same defect categories showing up repeatedly point to where a broader improvement project belongs.
How do you run a corrective action that satisfies 10.2?
Work a corrective action in this order and it will meet 10.2 and produce the records an auditor wants.
- React and correct. Contain the nonconforming product, protect the customer, and fix the immediate problem. Record what you did. This is correction, not yet corrective action.
- Decide whether cause action is warranted. Evaluate the significance: is this recurring, customer-facing, or high-risk? Not every nonconformity needs a full corrective action, and 10.2 lets you scale the response to the risk.
- Analyze the cause. Use a structured method to get past the symptom to the real cause, and check whether the same cause exists elsewhere. "Operator error" is not a cause.
- Implement the action. Change the process, the strongest actions error-proof the work rather than relying on people to remember. Update the affected documents and training.
- Review effectiveness. After a defined period, confirm with data that the nonconformity has not recurred and no new problem was created. If it recurred, reopen; do not close on the paperwork.
- Update and record. Update risks and opportunities if the corrective action changes your risk picture, adjust the QMS if needed, and retain the records of the nonconformity, the action, and the results.
Those six steps are 10.2 almost verbatim. Do them consistently and the same defects stop coming back, which is the entire point of Clause 10.
The numbers behind improvement
Improvement is where the cost of poor quality is either recovered or repeatedly paid.
- ISO 9001:2015 replaced the standalone preventive-action clause with risk-based thinking in Clause 6.1, so Clause 10 now centers on reactive correction and continual improvement rather than separate preventive action (ISO 9001:2015).
- Continual improvement is one of the seven quality management principles ISO 9001 is built on, and the standard treats it as an ongoing requirement rather than a one-time project (ASQ, ISO 9001).
- ISO 9001 is maintained through recurring surveillance audits over a typical three-year certification cycle, at which auditors look specifically for evidence that nonconformities are being corrected at the cause and that the QMS is measurably improving (ISO, The ISO Survey).
The difference between a plant that improves and one that just closes paperwork is visibility: can you see the same defect recurring across shifts, can you trend a corrective action's effect, can you tell whether an improvement stuck? When quality checks, exceptions, and downtime are captured digitally at the station, Clause 10 stops being a folder and becomes a feedback loop. That is what Harmony's operations intelligence gives the floor, without ripping out your QMS software. See a plant that closed the loop in our customer story. Clause 10 acts on what Clause 6 planned, and automotive suppliers face a stricter version of all of it in our IATF 16949 guide.