Quality Management and Safety Engineering (BSc) - MST 326
Quality Circles.  Kaizen (continuous improvement). Poka-Yoke.

Many types of teams [1, pp.310-311] exist within commercial organisations:

Quality Control Circles (QCC), now referred to as Quality Circles (QC)

The concept of Quality Circles is attributed to Kaoru Ishikawa in Japan in the 1950s. QC usually consist of a small group of personnel from the same department or function within the company who volunteer to meet regularly to identify, solve and implement solutions to work-related problems.  The Key guidelines for successful Quality Circles [2] include:

Peter Scholtes [3] has suggested that there are ten ingredients for a successful team:

  1. clarity in team goals
  2. an improvement plan
  3. clearly defined roles
  4. clear communication
  5. beneficial team behaviours
  6. well-defined decision procedures
  7. balanced participation
  8. established ground rules
  9. awareness of the group process
  10. use of the scientific approach

Ho [2] defines fifteen stages for the implementation of successful Quality Circles:

  1. management briefing to raise awareness of the QC process
  2. the feasibility of QC is analysed
  3. formation of a steering committee
  4. co-ordinator and in-house instructor are selected
  5. potential areas for initial QCs are selected
  6. QC presentations made to appropriate first-line supervisors
  7. co-ordinators and middle management trained on the process and their respective roles
  8. supervisors volunteer and receive training
  9. newly trained supervisors make QC presentations to the employees
  10. employees volunteer to join the circle and receive training
  11. the circle is formed and begins its work
  12. additional circles form as interest broadens
  13. circles discuss and systematically solve problems
  14. management ensure rapid implementation once solutions have been accepted by the QC
  15. management ensure appropriate and proper recognition of the QC team

and suggests the following code of conduct for discussion within the QC:

Where the company and employee organisations (unions) agree, employee participation and empowerment can convert QC teams into Self-Managed Teams (SMT).  Donovan [4] suggests that the process to achieve this is:

Kaizen (a culture of continuous improvement)

Many of the greatest opportunities for improving the performance of an organisation lie at the interfaces between individual defined functions.  A process perspective enhances understanding of the role of the sub-process within the greater system.  Many small and gradual improvements, combined with occasional large and rapid improvements and breakthroughs combine to produce continuous improvement.  Such improvements may well arise from significant simplification of the processes undertaken.  Deming ("improve constantly and forever") focussed on understanding suppliers and customers as crucial to planning for quality.  Ho [2] states that "by eliminating various root causes of problems in the process, variation decreases, thus increasing the quality of the output" and cites the Deming PDCA cycle as an elementary tool to achieve such change.

The kaizen strategy has been called "the single most important concept in Japanese management - the key to Japanese competitive success" [5].  It is a philosophy which subsumes all business activities and everyone in the organisation.  If the quality of the people is improved (perhaps by involvement, training and education rather than by replacement), improvement of the quality of the products will follow.  Any activity directed towards improvement is included within kaizen, including:

The Kaizen Institute [1, p.410] suggest that continual improvement may arise by:

Do note that continual improvement implies forever: ever increasing pressure from customers and the market place drives all companies and if the competition are continuing to make improvements, then over time your company can fall from its leading position.

Poka-Yoke (mistake-proofing) and Zero Quality Control (ZQC) [6]

Human beings tend to make mistakes and errors can thus inadvertently arise due to [1, p.617]:

In the early 1960s Shigeo Shingo introduced the concept of Poka-Yoke through the introduction of mechanical devices into assembly operations at Yamada Electric such that parts were prevented from being assembled incorrectly.  The key to the process is to stop the process whenever a defect occurs, define the cause and prevent recurrence.  Once the errors leading to defects have been identified, they can be addressed.  Poka-Yoke is especially useful in assembly work and in working practices in the service sector.  Where Poka-Yoke is fully implemented, statistical process control is not needed for zero-defect operations.

Many applications are deceptively simple, but have required a creative solution to a potential problem.  Examples of Poka-Yoke solutions to common problems include:

as well as John Grout's on-line everyday examples of Poka-Yoke.


  1. J Evans and W Lindsay, The Management and Control of Quality - Fifth Edition, South-Western/Thomson Learning, Cincinnati OH, 2001.  ISBN 0-324-06680-5.  PU CSH Library.
  2. PR Scholtes et al, The Team Handbook - How To Use Teams To Improve Quality, Joiner Associates Inc, Madison WI, 1988. second edition, 1998: ISBN 1-88473-111-2.  PU CSH Library.
  3. SKM Ho, Operations and Quality Management, International Thomson Business, 1999. ISBN 1-86152-398-x.  PU CSH Library.
  4. JM Donovan, Self-Managing Work Teams: Extending The Quality Circle Concept, Quality Circles Journal, March 1986, 9(3), 15-20.
  5. M Imai, Kaizen - The Key To Japan's Competitive Success, McGraw-Hill, New York, 1986.  PU CSH Library.
  6. S Shingo, Zero Quality Control: Source Inspection and the Poka-Yoke System, Productivity Press Inc, 1 May 1986.  ISBN 0-915-29907-0.  PU CSH Library.
  7. J Essinger, Jacquard’s Web – how a hand loom led to the birth of the information age, Oxford University Press, Oxford, 2004. ISBN 0-19-280577-0.

URLs for Quality Circles, Kaizen and Poka-Yoke (checked as live on 26 August 2004):

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Created by John Summerscales on 27 November 2004 and updated on 24-Jul-2014 12:26. Terms and conditions. Errors and omissions. Corrections.