What Is Lean Six Sigma?

What Is Lean Six Sigma?

Lean Six Sigma is a team-focused managerial approach that seeks to improve performance by eliminating resource waste and defects.

It combines Six Sigma methods and tools with the lean manufacturing/lean enterprise philosophy. It strives to eliminate the waste of physical resources, time, effort, and talent while assuring quality in production and organizational processes.

Simply put, Lean Six Sigma teaches that any use of resources that doesn't create value for the end customer is considered a waste and should be eliminated.

Key Takeaways

  • Lean Six Sigma seeks to improve employee and company performance by eliminating the waste of resources and process/product defects.
  • It combines the process improvement methods of Six Sigma and lean enterprise.
  • Lean Six Sigma helps to establish a clear path to achieving improvement objectives.
  • The Lean strategy was established by Toyota in the 1940s and attempts to streamline operational processes, from manufacturing to transactions.
  • Six Sigma originated in the 1980s and seeks to improve output quality by reducing defects.

History of Lean Six Sigma

Lean Six Sigma is a combination of Lean methodology and Six Sigma strategy. Lean methodology was established by Japanese automaker Toyota in the 1940s. Its purpose was to remove non-value-adding activities from the production process.

Six Sigma was established in the 1980s by an engineer at U.S. telecommunications company Motorola who was inspired by Japan's Kaizen model. It was trademarked by the company in 1993. Its method seeks to identify and reduce defects in the production process. It also strives to streamline the variability of the production process.

Lean Six Sigma emerged in the 1990s as large U.S. manufacturers attempted to compete with Japan's better-made products. The combination strategy was introduced by Michael George and Robert Lawrence Jr. in their 2002 book Lean Six Sigma: Combining Six Sigma with Lean Speed.

Companies can arrange for Lean Six Sigma training and certification from a wide selection of organizations that specialize in the approaches of Lean Six Sigma and Six Sigma.

The Lean Six Sigma Concept

The lean concept of management focuses on the reduction and elimination of eight kinds of waste known as DOWNTIME, an acronym formed by the words defects, overproduction, waiting, non-utilized talent, transportation, inventory, motion, and extra-processing. Lean refers to any method, measure, or tool that helps in the identification and elimination of waste.

The term Six Sigma refers to tools and techniques that are used to improve manufacturing processes. The strategy attempts to identify and eliminate the causes of defects and variations in business and manufacturing processes.

Six Sigma's DMAIC phases are utilized in Lean Six Sigma. The acronym stands for define, measure, analyze, improve, and control. It refers to the data-driven five-step method for improving, optimizing, and stabilizing business and manufacturing processes.

A Lean Six Sigma approach that combines Lean strategy and Six Sigma's tools and techniques highlights processes that are prone to waste, defects, and variation and then reduces them to ensure improvement in a company's operational processes.

Lean Six Sigma Techniques

The techniques and tools used to accomplish essential goals of the Lean Six Sigma strategy include:

  • Kanban workflow management practices such as work visualization and limited work in progress that maximize efficiency and promote continuous improvement.
  • Kaizen practices that engage employees and promote a work environment that emphasizes self-development and ongoing improvement.
  • Value stream mapping to analyze places to eliminate waste and optimize process steps.
  • The 5S tool to ensure that the workplace is efficient, productive, safe, and successful.

Benefits of Lean Six Sigma

  • By increasing the efficiency of important processes, companies can improve the work experience for employees and the customer experience for buyers. This can build loyalty inside and outside of a company.
  • Streamlined, simplified processes can increase control and a company's ability to capitalize on new opportunities quickly.
  • They can also lead to more sales and revenue, lower costs, and more successful business results.
  • Involving employees in a group or a company-wide efficiency effort can improve their skills (e.g., analytical thinking and project management), improve their growth opportunities, and boost camaraderie.
  • By preventing defects, companies save on the time, money, and human effort previously required to identify and eliminate them.
  • Ultimately, all components of the business process benefits—employees, customers, vendors, and the company.

Lean Six Sigma Phases

The DMAIC phases of Lean Six Sigma are Define, Measure, Analyze, Improve, and Control. They are used to identify and improve existing process problems with unknown root causes.


Define the problem from a company perspective, stakeholder perspective, and customer perspective. Figure out the quality expectations that customers have and the extent of the problem.


Examine the current process and how it contributes to the problem. Determine whether the process can meet the previously defined quality expectations of customers. Match each process step to your quality criteria. Support your measurements with actual performance data.


Examine all information gathered thus far to finalize the exact nature of the problem, its scope, and its cause.


Solve the problem and verify the improvement. Collaborate to structure a solution that eliminates both the problem and its cause. Use your data to ensure that the solution fits the issue at hand. Test the solution and derive performance data to support it.


Monitor improvement and continue to improve where possible. Finalize acceptable performance criteria. Establish a plan that can deal with variations that occur, sustain improvements, and prevent a reoccurrence of the original problem.

Lean Six Sigma Belt Levels

Lean Six Sigma training uses Belts to denote Lean Six Sigma expertise. The exact specifications for each Belt may differ depending on what organization provides the certification.

White Belt

A White Belt means an employee understands the meaning and goals of Lean Six Sigma. They know the terms associated with the methodology and report any process problems to colleagues with either Green or Black Belts.

Yellow Belt

A Yellow Belt implies that an employee understands essential Lean Six Sigma concepts, tools, and techniques. They report process problems to colleagues with either Green or Black Belts. They also can be part of project teams and receive Just-In-Time1 (JIT) training.

Green Belt

A Green Belt certifies that an employee has some expertise in Lean Six Sigma strategy and can launch and manage Lean Six Sigma projects. They can provide JIT training to others. They focus on the use of tools and the application of DMAIC and Lean principles.

Black Belt

A Black Belt is an employee with advanced Lean Six Sigma expertise who reports to Master Black Belts. They can be full-time, cross-functional project team leaders, as well as a coach or mentor to Green Belts. They are responsible for putting Lean Six Sigma changes into place.

Master Black Belt

An employee with a Master Black Belt has extensive Lean Six Sigma expertise is typically responsible for the Lean Six Sigma initiative. They can act as coach or mentor and monitor projects. They work with company leaders to identify efficiency gaps and training needs. They report to C-Suite executives.

1 Lean Six Sigma Just-In-Time training allows employees to focus resources on what customers need, when they need it, rather than building up unnecessary inventory.

Lean Six Sigma vs. Six Sigma

Lean Six Sigma and Six Sigma are two related strategies that can solve process problems. Both can help companies make noteworthy improvements in quality, efficiency, and use of time by analyzing the way their processes function. Both use the DMAIC phases/method. Both are based on creating a problem-solving workplace culture.

However, Six Sigma is focused on reducing defects and process variability to improve process output and quality to meet customer expectations. Lean Six Sigma is focused on reducing or eliminating the wasteful use of resources and defects to improve workflow and create more value for customers.

Lean Six Sigma combines aspects of Six Sigma (such as data analysis) and aspects of the Lean methodology (such as waste-eliminating tools) to improve process flow, maintain continuous improvement, and achieve business goals.

What Is the Meaning of Lean Six Sigma?

Lean Six Sigma is a process improvement strategy that seeks to eliminate inefficiencies in a company's process flow by identifying the causes of problems and developing solutions to address them.

What Are the 5 Principles of Lean Six Sigma?

Define, measure, analyze, improve and control are the five principles and phases of Lean Six Sigma. They're the steps practitioners take to create more efficient processes and a workplace culture that's focused on continuous improvement.

Why Is Lean Six Sigma Important?

Many consider it important for the measurable and consistent improvements in operations and business results that companies achieve using it. It also might be considered important because it combines the significant process streamlining of the Lean methodology of the 1940s with the Six Sigma data-driven approach of the 1980s.

The Bottom Line

Lean Six Sigma is a management approach and method that endeavors to eliminate any wasteful use of resources plus defects in production processes so as to improve employee and company performance.

It draws on the Lean concept of the 1940s established by Japan's Toyota to reduce waste and the Six Sigma strategy of the 1980s established by U.S. company Motorola to reduce defects.

By combining these teachings, Lean Six Sigma puts the best of both to work to streamline efficient operations and financial outcomes for all kinds of organizations.