Process-control systems (PCSs) are critical in optimising resource management and efficiency in various engineering applications. In South Africa, these systems have been implemented to enhance productivity across industries such as mining, agriculture, and manufacturing. A randomized field trial design was employed to assess the performance of PCSs under controlled conditions. Data from multiple sites were collected using standardised sensors and analysed for efficiency metrics such as productivity and resource utilization. The analysis revealed a significant improvement in efficiency gains, with an average increase of 15% in production output when PCSs were implemented compared to baseline conditions. PCSs have the potential to significantly enhance operational efficiency in South African industries. The randomized field trial provided robust evidence supporting their efficacy and scalability across diverse settings. Further research should explore long-term sustainability and cost-effectiveness of PCS implementation, while policymakers could consider incentivizing their adoption through supportive regulatory measures. Process-Control Systems, Randomized Field Trial, Efficiency Gains, South Africa, Engineering The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.