Six Sigma: Definition, Methods, and Tools

Understand what is Six Sigma and learn its methods and tools to help elevate your processes and output

Published February 18th, 2021

What is Six Sigma?

Six Sigma is a process improvement technique that involves the application of Six Sigma methods and tools in order to come up with ways to continuously improve processes, create new products and services, and reach near-perfect output with defects allowed to only 3.4 per million opportunities.

Applying Six Sigma in a business helps the organization gain control of the quality of its processes by implementing a measurable approach to identifying causes of defects and coming up with solutions to reduce output variation. This in turn leads to improved quality of products and services, increase in profit, and boost in employee morale.

In this article we will discuss two Six Sigma methodologies and Six Sigma management tools used by experts for continuous process improvement and near-perfect output.

What are the Six Sigma Methodologies?

While Six Sigma experts and consultants have come up with their own methodologies for implementing Six Sigma in different organizations and industries, DMAIC and DMADV are the two methodologies of Six Sigma that are most widely used.


An acronym that stands for Define, Measure, Analyze, Improve, and Control, DMAIC is a rigorous quantitative method for process improvement. A Six Sigma method that is best applicable for the improvement of existing processes or products, DMAIC is intended for processes or output that may be performing below expectations or specifications and are determined to benefit the most from incremental improvement.


DMADV is a Six Sigma method that stands for Define, Measure, Analyze, Design, and Verify. DMADV follows the first three steps as DMAIC only that the last two steps are specific for the intent of redesigning or creating new processes, products, or services.

To further differentiate between DMAIC and DMADV, here are descriptions for each acronym:

Define – Identify and define the problem that Six Sigma is trying to solve Define – Define the customer needs
Measure – Identify the metrics or measurable aspects of the process or product Measure – Identify product capability and specifications based on what the customer needs
Analyze – Conduct rigorous analysis of data to uncover areas for improvement or causes of defects Analyze – Determine how the product or process can achieve the desired specifications
Improve – Improve the existing process, product, or service Design – The second D in DMADV, design the process, product, or service based on the data analyzed
Control – Set specific steps to follow in order to produce and replicate the expected results Verify – Verify that the output is indeed performing or meeting the specifications and customer requirements

Six Sigma Management Tools

Each step of the DMAIC and DMADV methodologies will entail the need to utilize some or a combination of Six Sigma management tools. Here are some of the most popular Six Sigma management tools you can use according to the needs of your business:

FMEA Template

FMEA stands for Failure Mode and Effects Analysis and it is a systematic method of anticipating potential failures in business processes and mitigating their impact on customers. Use this FMEA template when improving existing process, product, or service using the DMAIC method and identify potential problems in order to prevent potential adverse effects on customers. FMEA usually starts with a brainstorming session of an experienced team and concludes with a re-analysis of risks after corrective actions have been applied. Empower the team to easily describe the process function, identify the mechanism of failure, and determine the risk priority number (RPN).

DMAIC Template

This DMAIC template can help as a guide in applying the DMAIC methodology as a root-cause analysis for process improvement. Use this DMAIC template to perform the following:

  • Define the project goals;
  • measure and record the the current performance of the process or product in order to quantify the problem;
  • analyze the data until the root cause has been identified;
  • improve the process or design with the intent to address the defects or areas for improvement; and
  • specify the monitoring and control systems to produce and replicate the desired results.

Root Cause Analysis (RCA) Template

Used in the analysis step of Six Sigma methodologies, Root Cause Analysis (RCA) is an approach in analyzing an identified problem and eliminating its root cause. RCA can help ensure the prevention of recurring problems, aiding in the improvement of business processes. Use this RCA template to analyze a recurring problem and help eliminate the root causes.

5 Whys Template

Use this 5 whys template designed to make it easier to uncover the very root cause of a problem by drilling down and asking the question “why?” until all logical questions are answered and the real cause of the problem is realized. Once the cause is identified Six Sigma experts can then formulate solutions that intend to prevent the same issues from recurring.

Kaizen Report Template

Use this kaizen report template to integrate the lean approach to your Six Sigma methodology. Define the project, select the category, uncover the root cause of the problem through RCA, and identify the improvement measures.

SIPOC Template

SIPOC or Suppliers, Inputs, Process, Outputs and Customer is a tool used to summarize and illustrate the end-to-end process of specific business functions and operations. Some use the opposite, COPIS, in which the customer is put first in the diagram. Use this SIPOC template to summarize all the processes involved in the creation of an output and utilize the information as a reference during brainstorming sessions for finding ways to improve or redesigning processes and products

Get Started With iAuditor for Six Sigma

From realizing a problem or customer need, formulating new processes, integrating solutions, and monitoring with the intent to continuously elevate processes and products in order to reach near-perfection with defects allowed to only 3.4 per million opportunities, Six Sigma can be very meticulous and exacting even for the experts involved, thus, a powerful tool such as iAuditor can help practitioners at every step of executing the chosen Six Sigma methodology.

SafetyCulture staff writer

Erick Brent Francisco

As a staff writer for SafetyCulture, Erick is interested in learning and sharing how technology can improve work processes and workplace safety. Prior to SafetyCulture, Erick worked in logistics, banking and financial services, and retail.

As a staff writer for SafetyCulture, Erick is interested in learning and sharing how technology can improve work processes and workplace safety. Prior to SafetyCulture, Erick worked in logistics, banking and financial services, and retail.