Critical success factors in implementing Green Lean Six Sigma (GLSS) for sustainable manufacturing: a systematic literature review

Purpose This study aims to identify critical success factors and formulate strategies for implementing Green Lean Six Sigma (GLSS) integrated with Industry 4.0 technology inclusively, to improve process efficiency, product quality and sustainability in the manufacturing sector, including the manufacturing industry. Design/methodology/approach This study used a Systematic Literature Review (SLR) approach with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. Findings The study’s results show that the success of GLSS is strongly influenced by technological readiness and a supportive organizational culture. However, the full automation approach is still difficult to be adopted by labor-intensive industries. Therefore, a hybrid Lean-Internet of Things (IoT) model that maintains the role of humans and is supported by real-time sensor systems and cloud-based dashboards is a strategic alternative. This approach enables early detection of production defects, increased efficiency and reduced defect rates. The Human–Cyber–Physical Systems (HCPS) concept proves to be relevant in integrating human and technological capabilities collaboratively. Research limitations/implications This study is limited to the literature in the last 15 years and has not tested direct empirical implementation in specific industries. Further studies can be conducted through longitudinal studies or trials in real manufacturing environments. Practical implications The findings provide strategic guidance for operational managers and policy makers in designing a GLSS implementation roadmap that not only focuses on digitization but also considers the readiness of human resources and organizational structures in industries that are not yet fully digitized. Originality/value The main contribution of this research is in introducing a more inclusive and applicable hybrid Lean-IoT based on GLSS model, and aligning sustainability principles with human engagement through HCPS-based production systems.