Source: Behrends and Rodrigue, 2015.
Urban logistics involves two main functional classes of flows:
- Producer-related flows includes industrial and terminal haulage, such as interregional and global freight flows, usually in unit loads such as containers and full truckloads, originating from or destined to terminals, manufacturing or distribution facilities. This form of flows is usually taking place in a massified form, benefiting from economies of scale.
- Consumer-related flows includes intra-urban urban freight flows, usually as part loads and parcels originating from distribution facilities and destined to commercial facilities or residential households.
Urban freight flows, like most freight flows, are imbalanced in their reciprocity. This is particularly the case for consumer-related flows that are usually unidirectional and related with empty backhauls. For instance, retail deliveries (most commonly from distribution centers) are one way freight flows with the delivery vehicle returning empty or with small loads of returned goods or recyclables (e.g. cardboard boxes). Commercial to residential freight flows are almost exclusively involving consumers carrying their purchases from stores to their place of residence by walking, car, public transit or cycling.