This paper offers an extensive review of the critical success factors (CSFs) for Lean and Six Sigma deployment, derived from recent literature. By employing a systematic methodology, relevant studies were analyzed, leading to the identification and organization of CSFs using the Affinity Diagram technique. The clustering analysis, which identified 89 CSFs, revealed three major categories that demand significant attention. Although the benefits of Lean and Six Sigma are well-documented, many organizations neglect its CSFs, jeopardizing successful implementation. This study underscores the importance of recognizing and addressing these factors to ensure the successful and sustained adoption of Lean and Six Sigma. The findings provide valuable insights for practitioners and researchers to enhance readiness and improve the implementation process of Lean Six Sigma methodologies, thereby achieving optimal efficiency.