Six Sigma Basics

If you have no idea what Six Sigma is, you’re not alone. Here’s a primer.

Six Sigma
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From a supply chain management ​quiz: A Six Sigma black belt might visit my company and say:

a.    Implement a kaizen event to optimize your workflow.

b.    That will be $400 per hour plus travel and lodging.


If you have no idea what a Six Sigma black belt is, you’re not alone. Motorola implemented the concept of Six Sigma in the mid-1980’s as a way to seek process improvements in its manufacturing operations. Since then, the term has become synonymous with process optimization.

In a nutshell, Six Sigma projects are disciplined, data-driven and designed to improve processes by identifying and removing the causes of defects or errors and minimizing variability. Six Sigma projects are usually led by professionals trained (and typically certified) in Six Sigma techniques. The Six Sigma vocabulary can sometimes be confusing, so here’s a primer to get you started. If you want a deeper dive, try this.

First of all, why’s it called “Six Sigma”? The term Six Sigma is derived from the statistical principle that states - if you start at your process’ mean value and you eliminate defects within six standard deviations of the mean and the nearest specification limit, you’ll virtually eliminate all defects or errors.​ If you’re not a statistician, think of Six Sigma looking at a bell curve and eliminating the errors within the thick chunk of the bell. 

Executive Leadership – Within any Six Sigma project, you’ll want Executive Leadership. This role can include the CEO or other top management. They are responsible for setting up a vision for a Six Sigma implementation. One important aspect of having Executive Leadership is the buy-in aspect of it. If you want a project to succeed, it’s critical that those in an organization understand why it’s important – and who it’s important to.

Champion – The Champion is the person in an organization who 'champions' a Six Sigma project, like a senior manager who ensures that it’s properly resourced and uses their authority to overcome organizational barriers. The champion sits a level below the Executive Leadership.

Master Black Belt – The Master Black Belt is an expert with extensive experience and technical expertise in all aspects of Six Sigma. The Master Black Belt is responsible for selecting, training and mentoring black belts within an organization. They’ll also ensure the Six Sigma program standards are maintained.

Black Belt – A Black Belt is a full-time professional and team leader responsible for the operation and outcome of a Six Sigma project. Black Belt training courses involve a month or more of classroom training – with a study focus in methods, statistical tools, and team skills. Black Belt training courses also require a completed Six Sigma project. Certified Six Sigma Black Belt qualification courses are offered by the American Society for Quality (ASQ) and other organizations.

Green Belt - A Green Belt has been trained in Six Sigma methodology and participates in projects as part of their full time job. They may either work as part of a team, led by a Black Belt, or lead smaller projects, with a Black Belt acting as mentor.

Project Sponsor - The Project Sponsor is a manager who can sign off on resources, defines objectives and evaluate outcomes. The Project Sponsor is sometimes the Champion or Executive Leadershop.

Big Y and Little y – The high level objective that a Six Sigma project seeks to improve is known as the Big Y . The Big Y is often used to generate little y operational objectives that need to be improved to hit the Big Y target.

DMAIC – the five main steps in the Six Sigma process; Define, Measure, Analyze, Improve and Control.


  • Define the customer and their expectations
  • Define the impacted business processes
  • Define the project boundaries
  • Create a process map
  • Define metrics, including Big Y and little y's
  • Form a project team
  • Develop a project charter


  • Gather data and measure the existing processes


  • Analyze the gathered data
  • Identify the gaps between existing and desired performance
  • Identify sources of variation
  • Decide on the processes to be improved


  • Propose solutions
  • Carry out pilot studies, test and evaluate the proposed solutions
  • Develop an implementation plan


  • Implement processes to ensure sustainable improvements
  • Develop procedures, control plans and train staff