# Industry 4.0 and Lean Six Sigma Integration: A Systematic Review of Barriers and Enablers
## 4 Review and Discussion
### Integration Enablers  
This section discusses the enablers of the LSS and I4.0 integration. By enablers, we mean facilitators or factors that make integration possible [65]. Table 3 presents the categories of enablers determined through a literature review. These categories are discussed below. **Efficient operations**--Although companies can directly implement I4.0 in their operations, the reviewed literature suggests improving process efficiency first [66]. This can be  
Figure 6: Primary industries identified by the reviewed articles. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Category** & **Integration Enablers** &
\begin{tabular}{c} **Articles Considering** \\ **the Enabler (\%)** \\ \end{tabular} \\ \hline \multirow{4}{*}{Collaborative culture} & Involvement of employees and other stakeholders & 22\% \\  & Top management support and commitment & 18\% \\  & Availability and openness of company staff & 4\% \\ \hline \multirow{4}{*}{Strategic orientation} & Investment in staff training & 27\% \\  & Investment in IT infrastructure & 16\% \\  & Integration of implementation approach with the business strategy & 8\% \\  & Mature understanding of I4.0 and Lean Six Sigma & 4\% \\  & High level of company maturity in the use of I4.0 and L & 3\% \\  & Availability of implementation patterns for integration & 1\% \\ \hline \multirow{2}{*}{Efficient operations} & Simplified processes & 5\% \\  & Standardised processes & 4\% \\ \hline \multirow{2}{*}{External stakeholders’ support} & Regulations for the protection and security of company data & 4\% \\  & Subsidies and seed funding & 1\% \\ \hline \multirow{2}{*}{Interconnected IT systems} & Interoperability of IT systems & 14\% \\  & Availability of reference architecture models & 3\% \\  & Flexibility of IT systems & 1\% \\ \hline \multirow{2}{*}{Literations} & Timely and accurate data availability & 1\% \\ \hline \hline \end{tabular}
\end{table} 
Table 3: I4.0 and LSS integration enablers. achieved by implementing L and SS tools/techniques before integration with I4.0 [33; 67; 68] and conducting process standardisation [23; 33]. As a result, no inefficiencies in the process are automated, and no money is wasted [66]. **Collaborative culture**--An organisational culture involving employees, suppliers, and customers is a crucial enabler for I4.0 and LSS integration. According to [64], this can boost the workforce's empowerment and collaboration in problem-solving activities. In addition, employee empowerment, regardless of job position, is a crucial aspect that helps employees to engage in improvements and offer solutions based on their expertise [42; 64]. Another factor that may facilitate I4.0 and LSS integration is management support. Indeed, [69; 70] indicated that when top management creates a supportive learning and proactive working environment, it builds trust and loyalty in the work team. **Strategic orientation**--Several strategic elements favouring the integration process have been suggested in the literature. For instance, in [23], the importance of implementation patterns for I4.0 and LSS integration was addressed. These patterns provide companies with information, for example, on I4.0 technologies to enhance the performance of LSS tools and techniques, and vice versa, as well as critical aspects to consider during the integration process. Another element that may facilitate overall integration is a solid understanding of I4.0 and L among company management [41; 66; 71]. This is an inherited enabler from the literature on Lean automation, encompassing aspects such as knowledge of I4.0 concepts, awareness of its related technologies, and understanding of the individual benefits of I4.0 and L. Furthermore, a high level of maturity in both approaches has been identified as an advantage for their integration [12]. Other critical factors favouring integration include linking the implementation approach to business strategies [39; 42; 72], investing in staff training [73] and IT infrastructure [72].