Applying PDCA. A Practical method.

“Defeats are merely repeats with better information.”


“Defeats are merely repeats with better information.”

By Orrin Woodward

The Deming cycle, also known as PDCA circle or spiral of continuous improvement, is a strategy of continuous improvement of quality in four steps, based on a concept devised by Walter A. Shewhart. It is widely used by quality management systems and information security management systems.

The results of the implementation of this cycle allow companies to comprehensively improve competitiveness, products and services, continuously improving quality, reducing costs, optimizing productivity, reducing prices, increasing market share and increasing market share profitability of the company or organization.

Applying PDCA


The activities of the process are established, necessary to obtain the expected result. By basing the actions on the expected result, the accuracy and compliance of the specifications to be achieved also become an element to be improved. When possible, it is convenient to carry out preproduction tests or tests to prove the possible effects.

  • Collect data to deepen knowledge of the process.
  • Detail the specifications of the expected results.
  • Define the activities necessary to achieve the product or service, verifying the specified requirements.
  • Establish the objectives and processes necessary to achieve necessary results according to the client’s requirements and organizational policies.

Planning tools

These tools can serve two purposes:

– To facilitate and standardize the methodology of project planning, activities and tasks.

– To help design products, processes and services according to the requirements and functions foreseen in the future.

Some examples of planning tools can be seen in the following list:

  • AMFE – Modal Analysis of Faults and Effects
  • Gantt chart – Planning and monitoring of activities and projects.
  • Intuitive Poka-yoke design method – Safe design.
  • QFD – Deployment of the quality function (Introduction) – Introduction to the analysis of needs and expectations.
  • Brainstorming – Participation of all interested parties.


Changes are made to implement the proposed improvement. It is usually convenient to do a pilot test to test the operation before making the changes on a large scale.


After a period foreseen in advance, the control data are collected and analyzed, comparing them with the requirements specified initially, to know if they have been met and, if necessary, to evaluate if the expected improvement has occurred.

Monitor the implementation and evaluate the execution plan documenting the conclusions.

Evaluation tools

The evaluation tools are used to control the current status of a project, process, product or service in order to have a detailed view of its status, evaluate it or look for ways to improve it later.

Some examples of evaluation tools are found in the following list:

  • Pareto diagram – The famous curve 80% -20% to organize data and focus efforts on the most important.
  • Correlation diagram – Graphic representation that shows the relationship of one variable with respect to another.
  • Ishikawa diagram – Study to locate the causes of the problems.
  • Scorecard – Management model, with a periodic information support for the management of the company’s processes.
  • Check list – Control Lists.


Based on the results obtained in the previous phase, we proceed to collect what we have learned and put it into operation. There are also usually recommendations and observations that usually serve to return to the initial step of Planning and so the circle will never stop flowing.

Currently some experts prefer to call this step “Adjust”. This helps people who start in the PDCA cycle to understand that the fourth step has to do with the idea of ​​closing the cycle with feedback to bring the results obtained to the objectives. Furthermore, this step “A” should not be confused with the set of actions (implementation) as a consequence of the deployment of the plans (developed in the second step, “D”, of “doing” or “carrying out the Actions”) .

Improvement tools

The tools for continuous improvement are designed to look for weak points in current processes, products and services. In the same way, some of them focus on identifying which are the priority areas for improvement or which can bring the most benefits to our work, so that we can save time and make changes only in the most critical areas.

Some examples of improvement tools can be found in the following list:

  • Value analysis – Orderly method to increase the value of a product or service.
  • Kaizen Method – Seeks a continuous improvement of all aspects of the organization.
  • Affinity diagram – Put together ideas or issues to organize and summarize grouping related ideas.