DMAIC
Definition
DMAIC (Define, Measure, Analyze, Improve, Control) is the primary Six Sigma problem-solving methodology, used to improve an existing process by systematically defining the problem, measuring current performance, analyzing root causes, implementing improvements, and controlling the new process.
DMAIC is the engine of Six Sigma's DMAIC-DMADV pair. Use DMAIC when the process exists and needs improvement; use DMADV when you're designing something new. The five phases work in strict order — you cannot skip or abbreviate them without undermining the rigor that makes Six Sigma effective.
Define: Scope the project. Write a problem statement and goal statement. Identify customers and what they require (CTQs — Critical to Quality). Build a project charter.
Measure: Quantify current performance. Establish a baseline metric. Validate the measurement system is reliable. Map the current process in detail.
Analyze: Find the root causes of the gap between current and desired performance. Use fishbone diagrams, 5 Whys, hypothesis testing, and statistical analysis. Don't jump to solutions — the Analyze phase is where most teams shortcut and fail.
Improve: Design and test solutions to the root causes identified in Analyze. Pilot the solution. Prove with data that it works. Use design of experiments (DOE) for complex multi-variable problems.
Control: Lock in the gains. Update the standard operating procedure. Set up monitoring (control charts). Train the team on the new standard. Hand off to the process owner.
DMAIC projects typically take 3-6 months and are led by a Green Belt or Black Belt. They generate significant whiteboard activity: process maps in Define and Measure, fishbone diagrams in Analyze, solution brainstorms in Improve, and control plan sketches at the end.
Examples
- Define: 'Customer wait time at service counter exceeds 8 minutes 30% of the time — goal is under 5 minutes in 95% of cases'
- Measure: time-stamping every customer interaction for four weeks; baseline is 9.2-minute average wait
- Analyze: fishbone reveals root causes are staffing gaps at peak hours and slow POS system login
- Improve: cross-train staff, stagger shifts, cache POS login sessions
- Control: install digital queue display showing real-time wait, monitor weekly, set alert at 7 minutes
Related terms
Snap a dmaic. Ship its actions.
BoardSnap turns any whiteboard — including this one — into a summary and action plan.