Six Sigma: literature review and key future research areas

It is a timely point to extensively review the literature on Six Sigma given the recent increased research interest. This paper reviews more than 200 Six Sigma papers, classifying them according to their research content and the research methodology employed. A comprehensive list of future research areas is given. Key examples are further development of a scientific foundation for the methodology; integrating Six Sigma with other methodologies such as adding Lean Tools; considering implementation issues in areas other than North America and Europe and furthering the debate on how to adapt the approach for use in a service context.