The last mile of parcel delivery – the movement from local depots to consumers – is becoming one of the biggest challenges in urban logistics. With booming e-commerce and fast delivery expectations, this stage is both the most costly and the most polluting part of the supply chain. Last-mile operations can account for more than half of total parcel shipping costs and are projected to raise urban delivery emissions by over 30 percent in major cities by 2030. Finding sustainable, efficient ways to organize these deliveries is therefore essential.
What the review does
A recent paper presents a review of 265 studies (2010–2025) on innovative ground-based parcel last-mile delivery (LMD) solutions, focusing on research that applies operations research (OR) methods such as optimization, mathematical programming, and heuristics. The study classifies different LMD innovations, links them to sustainability goals (economic, environmental, and social), and maps suitable OR techniques for each.
Innovative ground-based solutions are:
• Electric vehicles (vans, tricycles): key issues include battery range, charging logistics, and fleet design.
• Autonomous delivery robots: require new routing and scheduling models, plus attention to safety and public acceptance.
• Parcel lockers and pick-up points: shift delivery from doorsteps to shared facilities; research focuses on location and integration with delivery routes.
• Crowdsourcing or crowdshipping: leverages private individuals for deliveries; optimization models handle matching and routing under uncertainty.
• Freight-on-transit: uses existing public transport networks for parcel flows, integrating passenger and freight planning.
• Hybrid systems: combinations of the above, such as EVs combined with parcel lockers or ADRs, to balance efficiency and sustainability.
Operations research perspective
The paper develops a framework linking decision levels (strategic, tactical, operational) with sustainability goals (cost, emissions, service, equity, resilience) and appropriate OR techniques. For instance, energy-aware heuristics are used for EV routing, while stochastic or robust programming helps to manage uncertainty in demand or traffic. This structured view helps researchers and practitioners select the right modelling tools for their objectives.
Main findings
Each delivery innovation has unique operational challenges. Electric fleets require charging management, lockers demand location optimization, and robots need real-time coordination. The authors find that combining solutions can yield larger efficiency and emission benefits than isolated approaches, but the resulting systems are more complex to model and implement. Current research focuses heavily on cost and service; equity and resilience receive less attention.
Research gaps
Future research should emphasize hybrid solutions, empirical validation through field pilots, and inclusion of social aspects such as accessibility and fairness. More advanced modelling methods are needed to address large-scale, real-time, and multi-objective problems. The paper also calls for standardized reporting and transparent data for comparability.
Relevance for practice and policy
The review helps logistics operators understand which methods and innovations best support their sustainability goals. It also guides urban planners and policymakers in targeting investments in infrastructure such as charging networks or parcel locker systems. For researchers, it provides a roadmap of open challenges and opportunities.
In short, this review offers a comprehensive synthesis of sustainable last-mile delivery research from an operations research viewpoint. It shows that progress depends not just on technology, but on how cities and logistics providers combine and coordinate these solutions within real-world constraints.