What Are Six Sigma Belts All About?

All Over The Place

Training courses and certification exams for six sigma are all over the place. There are no generally accepted standards for either training courses or certification exams.

For example, I have found Certified Six Sigma Green Belt classes starting at $14.99 and going up to $8,400.00. This is clearly a situation of caveat emptor or buyer beware.

It’s ironic how a program, focused on reducing variation, has evolved into such uncontrolled confusion.

For this article, I’ll stick to standard six sigma. I won’t muddy the waters with lean six sigma, lean sigma, constraint sigma, or some other derivative.

Six Sigma Confusing

Let The Sun Shine

One ray of sunshine does light our way through the chaos.

There is general agreement on levels of knowledge, known as “belts”, and the roles people with these belts will take on six sigma projects. The most widely recognized six sigma belts and the corresponding roles are:

  • Yellow: subject matter experts and other project support roles
  • Green: manage projects, collect data, analyze data, design improvements, implement improvements, and monitor new processes
  • Black: lead major projects, ensure rigorous data analysis, coach teams in designing robust solutions, guide implementation of improvements, and monitor new processes until they are ingrained
  • Master Black: provide expert advice on overall program management and train new Black Belts

One additional role, which is not a belt, is the Champion. This is the executive sponsor who ensures the right projects are funded and solutions provide benefits to the organization.

6 Sigma Belts

No Ownership

The challenge with training courses and certification exams is understandable. No one “owns” the six sigma belt classifications.

Add in the fact of an immense body of knowledge, and you have an additional challenge of segmenting which concepts, terms, and tools should be allocated to each of the three belts.

At risk of aggravating every six sigma training provider, the following sections identify the body of knowledge which should be included in the curriculum for each belt.

6 Sigma Belt Curriculum

Yellow Belt

The curriculum for Yellow Belt training should be a general introduction to key concepts, terms, and tools.

A company specific training class should include the case for change and explore successful six sigma projects which have been completed.

The concepts, terms, and tools include:

  • Cost of Quality
  • Quality Definitions
  • Quality at the Source
  • Types of Inspection
  • Normal Distribution
  • Standard Deviation
  • Standard Work
  • Variation
  • Defects per Opportunity
  • Define Measure Analyze Improve Control (DMAIC)
  • Project Champion
  • Project Team Roles
6 Sigma Yellow Belt

Green Belt

The curriculum for Green Belt training should include a deeper dive on everything covered in Yellow Belt. In addition, there should be a well-defined six sigma project which walks through Define Measure Analyze Improve Control (DMAIC), includes data analysis, and addresses reducing defects per opportunity.

Learning can be enhanced and accelerated when the project is a scripted example which includes data and information designed for learning all of the required material.

The concepts, terms, and tools include:

+Historical Perspective
  • History of Continuous Improvement
  • The Quality Gurus
  • Total Quality Management
  • Critical Path Method
  • Critical Success Factors for Six Sigma
  • Gantt Chart
  • Proactive Sources
  • Problem Statement
  • Program Evaluation and Review Technique
  • Project Charter
  • Project Objectives
  • Project Risk Analysis
  • Project Team Roles & Responsibilities
  • Project Scorecard
  • Reactive Sources
  • Scope Creep
  • Stakeholders
  • Voice of the Customer
  • Affinity Diagram
  • Big Data (Introduction)
  • Cause and Effect Diagram
  • Check Sheet
  • Critical to Quality
  • Data Report (Simplified)
  • Fishbone Diagram
  • Focus Group
  • Ishikawa Diagram
  • Process Mapping
  • Run Chart
  • Spaghetti Diagram
  • Suppliers Inputs Process Outputs Customers
  • Value Stream Mapping (Introduction)
  • 5 Whys
  • Analysis Report (Simplified)
  • Brainstorming
  • Correlation Analysis (Introduction)
  • Flow Chart
  • Histogram
  • Mean, Median, Mode, and Range
  • Pareto Analysis
  • Root Cause Analysis
  • Scatter Diagram
  • Strengths Weaknesses Opportunities Threats (SWOT) Analysis
  • Balanced Scorecard
  • Benchmarking
  • Best Practices
  • Change Management
  • Force Field Analysis
  • Mistake Proofing & Poke Yoke
  • Recommendation Report (Simplified)
  • Sales & Operations Planning
  • Control Chart
  • Control Plan (Simplified)
  • Education & Training
  • Failure Mode Effects Analysis (Simplified)
  • Learning Curve
  • Policies
  • Risk Priority Number
  • Standard Operating Procedures
  • Statistical Process Control (Introduction)
  • Visual Controls
  • Work Instructions
+Introduction to Advanced Topics
  • Continuous Improvement
  • Design for Six Sigma
  • Dysfunctional Teams
  • House of Quality
  • Ideal Team Players
  • Lean Six Sigma
  • Lean Transformation
  • Minitab
  • Plan Do Check Act
  • Project Closure
  • Project Closure Plan (Simplified)
  • Project Failures
  • Quality Function Deployment
  • Six Sigma Belts
  • Team Development

Complex concepts, terms, and tools are only “introduced” during Green Belt training. Heavy statistical analysis tools are not appropriate.

6 Sigma Green Belt

Black Belt

The curriculum for Black Belt training should include a deeper dive on some material covered in Green Belt. In addition, there should be a sanctioned six sigma project which requires rigorous use of Define Measure Analyze Improve Control (DMAIC), includes complex data analysis, and addresses reducing defects per opportunity. The project must provide significant customer value and meet other stakeholder expectations.

Learning should be supported through coaching from an instructor who is a Master Black Belt and an executive sponsor who is a Six Sigma Champion.

The concepts, terms, and tools include:

  • Net Present Value
  • Project Reviews
  • Return on Investment
  • Toll Gate Reviews
  • Activity Network Diagram
  • Ambiguity
  • Binomial
  • Chi Square
  • Confidence Intervals
  • Continuous Variables
  • Data Report
  • Defects per Unit
  • Dependent Variables
  • Design of Experiments
  • Discrete Variables
  • Independent Variables
  • Interval
  • Opinions vs. Facts
  • Ordinal
  • Random Sampling
  • Sample Size Selection
  • Sampling Methods
  • Stratified Sampling
  • Test for Mean
  • Vagueness
  • Value Stream Mapping
  • Analysis of Variance
  • Analysis Report
  • Bias
  • Common Cause
  • Correlation Coefficient
  • Correlation Analysis
  • Correlation vs. Causation
  • Groupthink
  • Interrelationship Diagram
  • Kano Method
  • Linear Regression
  • Matrix Analysis
  • Matrix Diagram
  • Minitab
  • Multi-vari Analysis
  • Nominal
  • Normal Probability Plots
  • Poisson Distribution
  • Rolled Throughput Yield
  • Special Cause
  • Statistical Analysis Roadmap
  • Tree Diagram
  • Variation Trees
  • Agile Software Development
  • Capability Analysis
  • Hypothesis Testing
  • Multi-voting
  • Nominal Group Technique
  • Prioritization Matrices
  • Process Capability Indices
  • Process Decision Program Chart
  • Recommendation Report
  • Stage Gate Product Development
  • Control Plan
  • Failure Mode Effect Analysis (Design)
  • Failure Mode Effect Analysis (Process)
  • Process Components
  • Statistical Process Control
+Deep Dive on Advanced Topics
  • Big Data
  • Central Limit Theorem
  • Design for Six Sigma
  • House of Quality
  • Identify Design Optimize Verify
  • Lean Transformation
  • Multi-vari Planning
  • Plan Do Check Act
  • Project Closure Plan
  • Project Failures
  • Quality Function Deployment
  • Trends in Six Sigma
6 Sigma Black Belt

Master Black Belt

Great news for the Master Black Belt – there are just a few additional requirements. However, these require skills such as leadership, coaching, and teaching.

The additional requirements include:

  • Manage the six sigma program for an organization, business unit, local site, or whatever
  • Ensure six sigma projects are selected, scoped, and executed appropriately
  • Conduct training for Black Belts and coach them through their projects
  • Be the reservoir of knowledge for complex problem solving tools which are seldom used, but are very effective in the right situation
6 Sigma Master Black Belt


I don’t expect to clear up the confusion, in the worldwide market, for six sigma courses and certification exams. Most likely, I have made a number of experts turn red with anger. They are free to hold onto their own opinions.

My goal, for readers, is to provide a way to sort through the chaos and have a baseline for comparing six sigma courses and certification exams.

If you have a concept, term, or tool which is missing from the lists above, send me a message.

6 Sigma Belts

Want More?

Written by

Comments are closed.