DMAIC is the acronym for Define-Measure-Analyze-Improve-Control, the data-driven methodology for improving a product or process, underlying a Six Sigma quality initiative.
Define: describes the performance gap to be closed between the current state and desired state.
Measure: describes the method of measurement and collects data to describe the baseline performance.
Analyze: identifies the root cause of the performance gap.
Improve: develops, selects and implements improvements to the process.
Control: validates that the performance gap has been closed and establishes management controls and ongoing metrics to ensure that project gains can be sustained over time.
The DMAIC Methodology from ASQ: - http://www.asq.org/learn-about-quality/six-sigma/overview/dmaic.html