Lean Six Sigma Strategy at Work: Ups, Downs and Lessons Learned From Implementation - A Literature Review

Research work on Lean, Six Sigma and Lean Six Sigma has become increasingly present in the literature in the field of operations management and business excellence and has extended to other areas as the need for process improvement is more prominent. Whether it analyzes theoretical aspects regarding the development and the evolution of the two methodologies or of the most recent merge between the two, known as Lean Six Sigma strategy or simply Lean Sigma, or it presents results of studies undertaken in different industry or service sectors, the knowledge provided by the articles, books or studies currently available is vital to all researchers, specialists in the field and to all businesses. In this consideration we propose a detailed review of the most significant findings drawn from studies concerning the evaluation of the performance of Lean Six Sigma strategy as pure theory or as evidence from organizations performed in the time-frame 2003 to 2014 that seeks to underline the lessons learned from implementation and to question what is to be done in future researches.