From Kaizen to Digital Continuous Improvement: Linking Lean Practices with Sustainability Metrics

Charles Chikwendu Okpala¹, Okechukwu Chiedu Ezeanyim², Onukwuli Somto Kenneth³, Udu Chukwudi Emeka⁴

¹ Professor, Industrial/Production Engineering Department, Nnamdi Azikiwe University, Awka, Nigeria.
² Associate Professor, Industrial/Production Engineering Department, Nnamdi Azikiwe University, Awka, Nigeria.
^3,4 Research Scholar, Industrial/Production Engineering Department, Nnamdi Azikiwe University, Awka, Nigeria

Abstract

Continuous Improvement (CI), grounded in Kaizen and Lean management, has traditionally focused on efficiency, quality, and cost performance. However, growing sustainability pressures require organizations to demonstrate measurable environmental, social, and economic outcomes supported by robust data and transparent metrics. This article introduces and empirically illustrates a Digital Continuous Improvement (DCI) framework that systematically integrates Lean practices with digitally enabled sustainability measurement systems. Drawing on multidisciplinary perspectives from operations management, industrial engineering, information systems, and sustainability science, the study develops a process-level measurement architecture that links Kaizen activities to sustainability Key Performance Indicators through technologies such as IoT sensors, Manufacturing Execution Systems, and analytics dashboards. Using a data-driven illustrative case, the results show that digitally supported Kaizen interventions can achieve substantial and simultaneous performance gains, including reductions in energy intensity (approximately 18–25%), material waste (20–30%), and process lead time (15–22%), alongside notable improvements in safety, ergonomics, and employee participation. Methodologically, the study advances Lean–sustainability research by enabling direct attribution of sustainability outcomes to specific improvement actions with the application of high-resolution operational data. Theoretically, it reframes Continuous Improvement as a digitally enabled sustainability capability, while practically offering a replicable KPI taxonomy and analytics workflow for organizations that are pursuing ESG-aligned operational excellence. The DCI framework provides a scalable foundation for future empirical research and industrial application in the context of Industry 4.0.    

Keywords: Digital continuous improvement, Kaizen, Lean management, Sustainability metrics, Industry 4.0, Operational excellence, ESG performance.

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