What is DMAIC in 6 Sigma?

DMAIC methodology

Are you looking for a methodology to effectively improve your business processes and make data-driven decisions? DMAIC is the only solution. DMAIC (Define, Measure, Analyze, Improve, and Control) is a powerful Lean Six Sigma improvement methodology that is frequently used by certified Green Belts and above.

The acronym represents the process’s five phases, providing a clear sequence of steps to take and ensuring that projects are well-defined and improvements are founded on thorough root cause analysis and data collection. DMAIC is ideal for solving complex problems and making long-term improvements because it includes a variety of tools and techniques at each stage of the process. Don’t make managing continuous improvement projects a chore; instead, let DMAIC guide you through the process and help you succeed.

the five phases of DMAIC, Define, Measure, Analyse, Improve and Control

What is DMAIC?

DMAIC is the acronym for Define, Measure, Analyze, Improve and Control (DMAIC) is a powerful Lean Six Sigma improvement methodology often used by certified learn six sigma green belts and above. DMAIC is used for data-driven continuous improvement used to improve existing processes. Each letter of the acronym makes up the phases of the process providing guardrails for effective and efficient project management.

Why use DMAIC?

Often continuous improvement projects are not easy to manage particularly when you are looking to make business-critical decisions. This is what makes using the DMAIC project methodology useful as it provides a clear sequence of steps to follow which ensures projects are well defined and improvements identified are based on thorough root causes analysis and data collection.

What are the steps of DMAIC and how are they applied

DMAIC process tools and techniques used.

As we have already mentioned there are five key steps for a DMAIC improvement project. Define, Measure, Analyse, Improve and Control. Each stage has a clear individual focus and should be conducted in the specified order.


In the define phase of DMAIC, it is important to define the actual problem the DMAIC project is looking to resolve, the opportunity for improvement, the goals of the project and customer requirements (internal and external).

To achieve this a range of tools are used to support the development of the define stage which includes:

  • Project charter to define the focus and direction for the improvement team
  • SIPOC to define the suppliers, inputs, process, outputs and customers that are in the scope of the project
  • Voice of the customer to understand the feedback from the customers and their critical to quality (CTQ) metrics
  • Value Stream Map to provide an overview of the whole process that starts and finishes with the customers to support and analyse what is required to meet the customer needs.


In the measure phases of a DMAIC project, the focus is on measuring and understanding the current process performance to provide a baseline of how the process is currently performing.

There are a range of tools used in the measure phase to support the understanding of the current process performance which includes:

  • Process map to analyse what actually happens in the process recording the steps that happen in the process.
  • Process capability analysis to understand the process’s ability to meet the customer’s specifications.
  • Data collection of the frequency of the issues


Data Trends amico

In the analyse phase the focus comes to determining the root causes of the problem you are seeking to address by analysing the data you collected in the previous stage to better understand the problem and the causes of the problem. This allows more accurately identified solutions in the improve phase.

There are a range of tools and techniques that can be used in the analyse phase to support getting to the true root cause of the problem which includes:

  • Root cause analysis tools such as Cause and effect diagram and 5 Whys analysis.
  • Failure mode and effect analysis (FMEA) is used to identify the ways in which a product, process or service could fail and the effects the failures could have.
  • Pareto chart to understand the frequency of the problems or causes and to support prioritisation of the focus of the problem areas.
  • Multi-vai charts to detect different types of variation within a process.


Once you have done the steps of defining, measuring and analysing the current process and its performance, only then is it time to start improving the process. In the improve stage process performance is achieved by addressing and eliminating the root causes identified and verified in the analyse phase.

This stage of often an experimental phase with changes being introduced to the process and analysed using trials. The common tool used the improve stage usually include:

  • Design of experiments (DOE) for complex problems where a range of variables are required to be tested to understand how different inputs are impacting the outcome.
  • Solution piloting to trial implemented improvements and identify with data if the changes achieve the improvement set in the goal statement and the customer’s specifications.

At this point, if the improvements do not achieve the project goals a return to the analysis phase will likely be required.


Once you have made the required improvements to your project it is time to control the improvements. In the control phase of DMAIC tools and techniques are used to sustain the improvements that have been made ensuring the process performance does not return to its pre-improved state. This stage is vitally important within a project and should not be overlooked if the organisation wants to continually improve its process and not repeat the same improvements each time the previous improvement failed to be sustained or controlled.

There are a range of tools and techniques that can be used at this stage depending on the time of improvements you are looking to sustain. These tools include:

  • Quality control plan, which documents what KPIs need to be monitored to sustain the improvement and what actions need to be taken if the KPIs are not being met.
  • Standard operating procedures (SOPs) to document and standardise the improved way of conducting the process
  • Error proofing (Poka Yoke) to make process errors impossible by design or ensure that is instantly detectable if they occur.
  • 5S and visual controls to standardise the working environment.
  • Statistical process control (SPC) charts for monitoring process behaviour to be able to identify if the process goes out of control

When to use the DMAIC methodology?

The DMAIC methodology is ideal for fairly complex problems where it is difficult to understand the true root cause and requires a team to conduct thorough data analysis of the problem to identify the root cause and identify solutions to the problem. These projects focus on using a range of Lean and Six Sigma tools that are taught at the Green belt level but can often have a trained Lean Six Sigma Black Belt supporting the project. DMAIC projects due to the complexity also usually have a higher amount of resources dedicated to them to ensure the project’s success.


In summary, DMAIC is a powerful Lean Six Sigma improvement methodology used for data-driven continuous process improvement. Define, Measure, Analyze, Improve, and Control are the five phases of the process that provide guardrails for effective and efficient project management. DMAIC is frequently used by certified Lean Six Sigma Green Belts and above, and it is ideal for fairly complex problems where the true root cause is difficult to understand.

Project charter, SIPOC, Voice of the customer, Value Stream Map, Process map, Process capability analysis, Root cause analysis, Failure mode and effect analysis (FMEA), Pareto chart, Multi-vai charts, Design of experiments (DOE), Solution piloting, Quality control plan, Standard operating procedures (SOPs), Error proofing, 5S and visual controls, and Statistical process control (SPC) charts are among the tools and techniques employed by the methodology. DMAIC’s goal is to identify and eliminate the root causes of problems while also maintaining process improvements.



Daniel Croft

Daniel Croft

Daniel Croft is a seasoned continuous improvement manager with a Black Belt in Lean Six Sigma. With over 10 years of real-world application experience across diverse sectors, Daniel has a passion for optimizing processes and fostering a culture of efficiency. He's not just a practitioner but also an avid learner, constantly seeking to expand his knowledge. Outside of his professional life, Daniel has a keen Investing, statistics and knowledge-sharing, which led him to create the website learnleansigma.com, a platform dedicated to Lean Six Sigma and process improvement insights.

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