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This is my last post in the LEAN series that I have written about over the last few weeks. We talked about an overview of LEAN initiatives, What are the Elements of 5S, an introduction to Kaizen as well as What is KANBAN. Today I talk about one of the most searched and talked about parts of lean and answer the question, “What is Lean Six Sigma?” Please feel free to comment below on your thoughts about LEAN in both the workplace ,but also in manufacturing, supply chain, and logistics, in the comments section below, or feel free to email me at

What is Lean Six Sigma?

There is always a better way to do anything….hey, why not combine LEAN initiatives with increasing quality? How can we accomplish this to exceed our customer’s expectations and add value , let’s answer your question “What is Lean Six Sigma?”

So how did it become Lean Six Sigma?

Using additional problem-solving techniques can help solve a larger number and variety of business problems. Starting in the 1980’s, consultants trained in both techniques realized the connection between Lean and Six Sigma and began to push for the combination of the two (2) tools of Six Sigma (focused on improving quality) and Lean (focused on removing waste).

A combined management approach, LSS (Lean Six Sigma) amplifies the strengths and minimizes the weaknesses of both approaches when used alone.

what is lean six sigma dmaicIncreasingly popular, Lean Six Sigma first emphasizes the use of Lean methodologies and tools to identify and remove waste and increase process velocity, then follows that with the use of Six Sigma methodologies and tools to identify and reduce or remove process variation using Value Stream Mapping and root cause analysis reviewed in the last two (2) LEAN series articles.

Most organizations that run quality initiatives within a company now choose to use Lean Six Sigma rather than just one or the other methodology to gain a greater impact on the business.

Summary: remove all waste and improve throughput to the customer with LEAN and use Six Sigma to reduce process variation and improve quality. Common sense?

We have spent a lot of time reviewing LEAN, per se, like 5S, Kanban and Continuous Improvement or Kaizen initiatives. Basically the key to lean is to eliminate all waste. There are, as we reviewed, many kinds of waste. 5S is an organizational tool, Kanban is a pull system to eliminate large inventories which can be wasteful and improve throughput to the customer and continuous improvement/Kaizen are concepts to improve all operations daily and get all employees involved. Sustainability, maintenance and control of these system implementations are critical so employees do not fall back to old informal systems once the company has made the paradigm shift to LEAN initiatives. So, it’s time to shift to explaining Six Sigma.

What is Lean Six Sigma Philosophy?

Six Sigma is a management philosophy developed by Motorola that emphasizes setting extremely high objectives, collecting data, and analyzing results to a fine degree as a way to reduce defects in products and services. The Greek letter sigma is sometimes used to denote variation from a standard. The philosophy behind Six Sigma is that if you measure how many defects are in a process, you can figure out how to systematically eliminate them and get as close to perfection as possible or known as zero defects in the past before Six Sigma was developed. In order for a company to achieve Six Sigma, it cannot produce more than 3.4 defects per million opportunities, where an opportunity is defined as a chance for nonconformance. This is very close to perfection or zero defects and is difficult to attain. It takes much discipline and focus.

There are two Six Sigma processes: Six Sigma DMAIC and Six Sigma DMADV, each term derived from the major steps in the process. Six Sigma DMAIC is a process that defines, measures, analyzes, improves, and controls existing processes that fall below the Six Sigma specification. Six Sigma DMADV defines, measures, analyzes, designs, and verifies new processes or products that are trying to achieve Six Sigma quality. All Six Sigma processes are executed by Six Sigma Green Belts or Six Sigma Black Belts, which are then overseen by a Six Sigma Master Black Belts (SSMBB), terms created by Motorola.

what is lean six sigma dmadvSix Sigma proponents claim that its benefits include up to 50% process cost reduction, cycle-time improvement, less waste of materials, a better understanding of customer requirements, increased customer satisfaction, and more reliable products and services. It is acknowledged that Six Sigma can be costly to implement and can take several years before a company begins to see bottom-line results. Texas Instruments, Scientific-Atlanta, General Electric, and Allied Signal are a few of the companies that practice Six Sigma.

The classes for Six Sigma certification are lengthy and difficult as you go through the different belt levels. There are different levels of Six Sigma belt training and certification: Yellow Belts, Green Belts, Black Belts and Master Black Belts. Of course SSMBB (Six Sigma Master Black Belt) is the most difficult level to attain. Certifications should be renewed by re-testing each year to retain the original education or to move up to the next belt level. A top management VP should be accountable and responsible for this Six Sigma program as it should be a top down program with proper management focus, discipline, maintenance once, and control.

DMAIC: Define, Measure, Analyze, Improve and Control can be used for any root cause problem by using these steps to solve the problem. Cross-functional teams using DMAIC can solve many internal programs.

What guides what problems to be solved? The use of VOC or Voice of the Customer is used to drive Six Sigma projects. Questionnaires are sent to customers asking for input on how to improve your company to exceed the customer’s expectations. These replies are reviewed by the VP in charge of Six Sigma and the SSMBBs. They are then delegated to Six Sigma Black Belts and their teams. What priorities are used? Pareto’s 80/20 principle is used to review projects where 20% of the projects are 80% of the total and have the biggest impact on the company and their customers. These projects also add the biggest value to the company’s products, and eventually to their customers.

Summary of What is Lean Six Sigma

This is a general overview of Six Sigma. It is scientific and used by Engineering/Quality Assurance in many cases and goes into statistics much deeper than this overview, but this gives you a general idea of the Six Sigma process.

Critical factors:

Implementing LEAN in your company will take time. In some cases it takes a couple of years or more. Yearly re-certification of all concepts will be necessary. Weekly audits are necessary to maintain and control all LEAN implementations. Many group meetings will occur to solve critical issues that arise. Leaders in each department are necessary in focusing on maintaining the implementations. Key Performance Indicators (KPIs) should be set as goals, like, 10% productivity improvement in “X” number of months. An overall project plan would be very helpful for each phase of LEAN.


Without looking back at the previous articles in the LEAN series:

  • What does LEAN, in general, mean to you?
  • How would you implement 5S?
  • Why does KANBAN reduce inventory, and what is another name for KANBAN?
  • Do you practice Continuous Improvement/KAIZEN daily? If not, why not?
  • If you had to define Six Sigma in general, what would you say?
  • What is the most important aspect of ALL of these LEAN initiatives?

If you cannot answer these questions, or have comments about them, contact Chuck Intrieri: