PDCA (Plan Do Check Act) Cycles refers to the PDCA wheel (Figure 1) and the continuous motion that PDCA requires. PDCA is not as easy as it sounds but, if you are interested in ISO 9001 Quality Management Systems (QMS), then you will find that an ISO 9001 PDCA cycle is the solid foundation. Master PDCA and you will become the master of your ISO 9001 QMS.

ISO 9001 PDCA Cycle

Figure 1. PDCA Wheel

ISO 9001 PDCA Cycle

Plan Do Check Act was developed by Dr. Walter Shewhart, one of the top ten quality gurus. Dr. W. Edwards Deming preferred to call it PDSA or Plan, Do, Study, Act because he felt that “check?” emphasized inspection over analysis. Most people spend most of their time on the first two, Plan and Do, and tend to neglect the Check and Act parts. An ISO 9001:2015 QMS is a balanced system and to keep your ISO system working effectively you need to value each PDCA element equally and not favor one (i.e. Plan, Do) over the other (Check, Act).

We have written a lot about PDCA in the past. Now let’s take a look at PDCA as it relates to ISO 9001 by breaking down the ISO 9001 standard into its main elements and then assigning them to each part of the PDCA process. What you see is that each clause of the ISO 9001 standard contains a planning step, clause 7 is focused on doing, and clause 8 is focused on checking and acting. What clause do you think people have the most trouble with?

Clause 9 is the most troublesome because it is focused on checking and acting. People get more satisfaction in planning and doing then they do in checking and acting. It is just human nature. So, to master ISO 9001:2015 you have to break the habit and budget more time for the checking and acting steps of clause 9. Now let’s take a look at each PDCA element and see how ISO 9001 aligns with Plan Do Check Act.


Your business should have an annual planning cycle that produces business plans that contain your: interested parties, vision/mission/quality policy, operational objectives, budgets, risk management actions, documented information standards, milestones, and new product/market/process introductions. These are all planning elements. ISO 9001 calls out these planning elements in seven areas.

  • Maintain QMS (4)
  • Document QMS (7.5)
  • Leadership (5)
  • Planning (6)
  • Manage Resources (7)
  • Plan Product Realization (8.1)
  • Control Monitor & Measurement Equipment (7.1.5)


Your do steps are more frequent, possible occurring on a monthly cycle that produces data records for measurement and analysis as a result of executing the annual plans. A lot of your doing is focused on clause 8, Product Realization. Most of your documented information is produced in clause 8.

  • Competence (7.2)
  • Design, Develop, Realize (8)
  • Purchasing (8.4)
  • Product & Service Provisions (8.5)


Once you have data from your doing steps you need to analyze or study the data (remember Deming’s PDSA reminding us to Plan, Do, Study, Act). We do not want to check to see if a step was done or check to see if data was produced. This is nothing but inspection. We need to analyze and understand what the data is telling us. We do this by converting the data into information.

The ISO 9001:2015 standard clearly defines various check processes, which are cycles of measurement and analysis to determine how well the organization is executing the annual plans.

  • Management Reviews (9.3)
  • Monitor & Measuring (9.1)
  • Customer Satisfaction (9.1.2)
  • Internal Auditing (9.2)
  • Data Analysis (9.1.3)

These are not one-time events. These check processes continuously occur, which brings to mind trend lines on charts as a way to convert data into information.

A monthly or quarterly check event is very realistic, although many companies choose an annual audit, management review or customer satisfaction survey as a sufficient check on the ISO 9001 QMS. I guess if you have an incredibly stable business model with little to no competition and a static environment, industry or market then maybe you can get away with an annual check. Are there any businesses like that anymore?


Actions taken — without undue delay — to close the gap, identified during measurement and analysis, between the annual plans and the data records produced during execution. Of course there is an element of act in the management reviews because after you review the required inputs you are supposed to assign action items to individuals to take the necessary corrective actions (and maybe preventive actions).

ISO 9001 has a few clear action steps like isolating nonconforming product, taking corrective action, and maybe preventing risk too.

  • Nonconforming Product (8.7)
  • Corrective Action (10.2)
  • Risk Management (6.3)? (I know some of you want this here)

ISO 9001 PDCA cycle is not a singular thing. It is actually a series of embedded PDCA cycles. Clause 8 is not just about doing. Product realization is itself an ISO 9001 PDCA cycle that starts with planning requirements and realization needs. Next comes development (doing), development reviews (checking), and finally development revisions (actions). This same Plan Do Check Act cycle is occurring within training, documentation, purchasing, auditing, corrective action, etc. The whole concept of continuous improvement relies on PDCA.

Seven Quality Management Principles

The Seven Quality Management Principles of ISO 9001:2015 utilize the philosophy of the process approach. This Plan Do Check Act cycle centers around thees principles, which are used by management as a guide toward improving performance and identifying the main elements needed in a good and robust quality system.


Organizations depend on their customers and therefore have to understand their current and future customer needs, meet their customer’s requirements and strive to exceed their customer’s expectations.


Leaders establish a unity of purpose and the direction of the organization. They need to create and maintain an internal environment in which people can become fully involved in achieving the organization’s objectives.


People at all levels are the essence of an organization. Their full involvement creates opportunities for their abilities to be used for the organization’s benefit.


A desired result is achieved more efficiently when activities and related resources are managed as a process, which has a beginning, middle and end.  Inputs are clearly transformed into outputs, repeatedly.


Continuous overall performance improvement is the objective of a successful long-term organization.


Effective decisions are based on solid information and objective data analysis.


An organization, its suppliers, and stakeholders (interested parties) are interdependent and a mutually beneficial relationship enhances the ability of both to create value.

The Seven Quality Management Principles of ISO 9001:2015 utilize the Plan Do Check Act cycle as a guide toward improving performance and using the main elements needed in a good and robust quality system.

Check out Bizmanualz Internal Auditor Training programs for more information on building Lean ISO Quality systems, creating well-defined processes, or getting more value out of your quality management system.