The DMAIC Cycle - 5 Phases of Lean Six Sigma

DMAIC is the problem-solving methodology behind Lean Six Sigma. As a cycle, it consists of five vital actions:


Project selection is crucial for success

Before beginning any process improvement project, it’s vital that you choose projects that are good candidates for improvement. This will set you up for success. A good project for improvement will always:

  • Have an obvious problem within the process

  • Have the potential to result in increased revenue, reduced cost or improved efficiency

  • Have collectable data

DMAIC (Lean Six Sigma) is also a system of management that results in a steady pipeline of projects that are ready for improvement. There are obstacles to smooth operations in any business, and Lean Six Sigma provides guidelines to help you select the right projects at the right time. Once projects are selected, you and your improvement team(s) can use DMAIC to further refine the projects and deliver quantifiable, sustainable results.

 1.) Define: What problem would you like to fix? 

The Define Phase is the first phase of the Lean Six Sigma improvement process. In this phase, the leaders of the project create a Project Charter, create a high-level view of the process, and begin to understand the needs of the customers of the process. This is a critical phase of Lean Six Sigma in which your teams define the outline of their efforts for themselves and the leadership of your organization.

2. Measure: How does the process currently perform? 

Measurement is critical throughout the life of the project and as the team focuses on data collection initially they have two focuses: determining the start point or baseline of the process and looking for clues to understand the root cause of the process. Since data collection takes time and effort it’s good to consider both at the start of the project.

3. Analyze: What does your data tell you?

This phase is often intertwined with the Measure Phase. The data collection team may consist of different people who will collect different sets of data or additional data. As the team reviews the data collected during the Measure Phase, they may decide to adjust the data collection plan to include additional information. This continues as the team analyzes both the data and the process to narrow down and verify the root causes of waste.

4. Improve: How will you fix the problem?  

Once the project teams are satisfied with their data and determined that additional analysis will not add to their understanding of the problem, it’s time to move on to solution development. The team is most likely collecting improvement ideas throughout the project, but a structured improvement effort can lead to innovative and elegant solutions.

5. Control: Do you sustain the newly achieved improvement? 

This phase is a mini version of process management. The team has been building a form of infrastructure throughout the life of the project, and during the Control Phase they begin to document exactly how they want to pass that structure on to the employees who work within the process.


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