Kaizen: An Introduction to Continuous Improvement

Toyota's Taichi Ohno introduced kaizen, meaning "continuous improvement", at Toyota as a tool in the development of Just In Time manufacturing. Kaizen aims to improve all aspects of a company, including productivity, quality and employee satisfaction.

Kaizen, which literally means "continuous change and improvement" or "good wisdom", is a management practice that seeks ongoing incremental improvements as suggested by employees at every level of a company. This stands in contrast to expecting either managers or outside consultants to lead the way in short-term blitzes or dedicated projects. Kaizen also expects that most of its changes will not require massive capital investments, and that employees will readily adopt the changes because they were recommended from the grass roots.

A significant principle is that each employee has the responsibility and authority to suggest improvements.

Continuous improvement might use the acronym FEE:

  • Feedback is the input, whether from the internal employees or external customers
  • Efficiency is the goal: to eliminate wasted or misplaced effort
  • Evolution is the process: to make small changes rather than to revolutionize the process

Of course, once small changes have been made, there will be new feedback, to be analyzed for new potential changes in pursuit of efficiency.

While "grass roots" may imply that kaizen is unstructured or spontaneous, the usual practice is to set kaizen committees or teams and schedule this work as part of the daily or weekly routine.

This article is an introduction, covering the following:

  • A Brief History of Kaizen
  • The Scope for Kaizen Improvements
  • The Scope for Kaizen Participation

The next four articles deal with the stages in a Deming cycle, which is key to a kaizen program:

  • Step One of the Deming Cycle: Standardize Each Operation       
  • Step Two of the Deming Cycle: Measure Each Operation                                           
  • Step Three of the Deming Cycle: Evaluate Each Operation           
  • Step Four of the Deming Cycle: Improve Each Operation                         

A Brief History of Kaizen

The American occupational forces had the task of helping Japan recover after World War Two. Lowell Mellen and W. Edwards Deming arrived in Japan in the early 1950s to continue consulting Japanese business managers in statistical control processes.

As part of developing the "Toyota Production System", kaizen was adopted in an effort to maximize the potential for improvement through engaging the entire workforce in improving quality

Central to kaizen is the Deming cycle, also known as the Shewert cycle or Plan/Do/Check/Act (PDCA) cycle:

  • Standardize an operation: document the required outputs (size, weight, etc.) and the steps in the process
  • Measure this operation to determine cycle time and other relevant statistics
  • Compare the output to the requirements
  • Plan incremental changes to better meet the requirements or to improve the cycle time
  • Repeat the cycle, beginning by standardizing the changed operation

Since then, kaizen has often been integrated into other general manufacturing process philosophies. Often those philosophies will guide the nature of the improvements. For example, achieving the Six Sigma reduction in variance may require ongoing improvements in measuring outputs or maintaining equipment; the goal is to minimize defects. Lean manufacturing's goal may be to find ways to reduce inventory.

The Scope for Kaizen Improvement

A good starting point is to ask what is the scope for kaizen improvement? Can it be used only in manufacturing? Is it limited to cost cutting?

The answer is "No, kaizen has an extremely broad scope".

Here are some areas that may be amenable to continuous improvement:

  • Improving work flow by placing materials in easy reach, or adding a ramp to move outputs
  • Improving safety by placing guards or two-hand switches on presses
  • Improving quality with poka-yoke ("foolproof") methods, such as jigs to ensure parts can only be placed correctly before assembly
  • Designating a five-minute cleanup or maintenance step as the end of each shift at each machine
  • Adding a customer feedback opportunity to each web page, sales contract or telephone script

 Notice that many of these ideas can save money by saving on labour, rework or machine repairs. Some may involve expenses, such as losing those five minutes of production in return for cleanup or maintenance. Adding a customer feedback loop may well be expensive if someone actually has to review and respond to the customers.


The point, however, is that kaizen should be applied to every area of a company and for a variety of purposes including efficiency, safety, quality and customer service.

The Scope for Kaizen Participation

Participation in kaizen should be extended to all employees, in cross-functional teams. This allows for a variety of viewpoints. For example, a dialogue between departments might include the following. "It would help me if you could stamp the time and date on the worksheet before you pass it to my department". "What's wrong with using ‘first-in, first-out' so you don't need to check the date"? "Then we would need to reorganize the storage area". By presenting alternatives that favour different interest groups, it is more likely that an improvement will help all the parties involved.

Kaizen can include outside stakeholders, such as suppliers or customers. Whether pursuing efficiency or quality, small changes with these outside partners can lead to significant improvements.

Please continue to the next article describing the first steps in implementing kaizen.

By Oskar Olofsson