The objective of this study was to analyze points of convergence and divergence between the Theory of Constraints, Lean Manufacturing and Six Sigma, when used in an integrated manner for the continuous improvement of existing productive systems. The study's main focus was to search the literature and identify the characteristics of exclusion and the similarities between the three approaches when applied in an integrated manner to productive systems. A broad literature search encompassing the period 1995-2011 was conducted on the main national and international databases, seeking to identify the topic's state of the art research. The results of this study suggest that the Theory of Constraints, Lean Manufacturing and Six Sigma have many complementary elements that overlap their divergent points and that a vast field of research exists on this issue for future exploration. As a result, the study presents a critical analysis of 28 comparative criteria, relevant to the understanding of the three approaches, and concludes with a research agenda on the topic, based on identified gaps.
Theory of Constraints; Lean Manufacturing; Six Sigma; Continuous improvement
