Driving sustainable transportation through digital transformation, vehicle route optimization and continuous improvement: a conceptual framework for enhancing environmental and operational performance

Purpose This study explores the integration of digital technologies, vehicle routing optimization and continuous improvement principles (Lean and Six Sigma) to collectively enhance transportation efficiency and reduce negative environmental impacts. It aims to clarify how these complementary approaches contribute to reducing greenhouse gas (GHG) emissions, fuel and energy consumption and routing inefficiencies. Design/methodology/approach A systematic literature review (SLR) was performed, examining 87 resource materials from SCOPUS. The review synthesizes research on digital technologies, green vehicle routing and continuous improvement and identifies key performance indicators (KPIs) and critical factors associated with environmental sustainability and operational efficiency in transportation systems. Findings The study develops an integrative conceptual framework that positions digital technologies as enablers of data availability, real-time visibility and predictive decision-making, vehicle routing optimization as the operational execution mechanism translating data into emission-reducing routing decisions, and continuous improvement, operationalized through Lean Six Sigma, as a sustaining mechanism that supports process stability and long-term environmental performance. Environmental KPIs such as fuel and energy consumption, emissions and route efficiency, link these elements and enable systematic performance monitoring. The findings suggest that integrating these components can reduce unnecessary trips, idle time and resource waste while improving operational efficiency and environmental outcomes. Research limitations/implications The framework is conceptual and requires empirical validation across different transportation contexts. Practical implications The framework supports practitioners and decision-makers in implementing targeted strategies to achieve both operational improvements and environmental sustainability goals. Originality/value This research integrates digital transformation, continuous improvement (Lean and Six Sigma) and vehicle routing optimization into a unified framework for sustainable and green transportation, addressing a fragmented gap in previous research.