Six Sigma is a statistical quality control process that aims for a near-zero defect rate of 3.4 defects per million opportunities. It has five implementation steps -- define, measure, analyze, improve and control (DMAIC). The defect opportunities are first defined. The defect rate is then measured and analyzed. Processes are improved to reduce the defect rate. These improvements are sustained, verified and controlled in the final step. Effective Six Sigma implementation depends on leadership, project selection, infrastructure and change management.
Leadership from senior management ensures that the time, money and staff resources needed for a successful Six Sigma implementation are available. Management commitment also facilitates the restructuring and cultural change necessary for incorporating quality in every process step.
Six Sigma implementation is effective when projects aligned with a company’s strategic objectives are selected. Project size is also an important factor -- the selected project should be large enough to make a measurable impact, especially on the profit margin, but small enough to be manageable. The selected project should also be a fit with Six Sigma's DMAIC approach, meaning it should have defects that can be measured, analyzed and reduced.
A well-trained human resources infrastructure is needed for successful Six Sigma implementation. A separate group or department, consisting of members from various business units, should be responsible for coordinating all Six Sigma activities in an organization. This group should include Champions -- usually senior managers -- who understand Six Sigma principles and serve as guides for the practitioners; Black Belts -- with extensive training in the technical aspects of Six Sigma -- who act as teachers and mentors; Green Belts, who are usually project leaders with part-time Six Sigma roles; financial analysts, who quantify the bottom-line results; and external consultants, who provide technical expertise and training services.
Effective Six Sigma implementation also requires an IT infrastructure to help in decision making. It should support the data collection process, assist in data communication and sharing across the organization, and provide an easily accessible interface for all current and completed Six Sigma projects in order to promote organizational learning.
Successful Six Sigma implementation requires a fundamental change in culture. As with all change management initiatives, there will be organizational resistance. Some employees will have difficulty understanding the statistical concepts underpinning Six Sigma -- they will require technical training. Some may resist based on past history of quality improvement initiatives gone wrong, while others will dismiss it as the latest management fad. Management leadership will play an important part in communicating the importance of Six Sigma initiatives to the organization’s strategic objectives.