Six Sigma method is now one of the most used approaches in the Quality Management field because its benefits
coming from the improvement of the process outputs quality by identifying and removing the causes of defects and variability in
manufacturing and business processes. Thus, literature on the SS topic is exponentially increased during last decades; the vast
number of works on
the six sigma field represents a good opportunity for a structured literature review of the articles, in order to know the evolutions
of the concept, the fields of its application and possible evolution for further studies. The literature review has been carried out
by using a chronological review of the main SS approaches developed both for large and small companies, in order to highlight
particular aspects of the SS literature and some applications of the SS methodology. The evaluation of the papers found in
literature is carried out through a Strengths-Weaknesses criterion.