In a Fordist production system, supply chains are often discontinuous and subject to delays. Links between different functions imply the accumulation of inventory (raw materials, parts, and manufactured goods) before their usage (processing, manufacturing, and distribution). The high output levels of an assembly line require warehousing of all required parts in the vicinity. This cannot occur without a stable and constant demand, which is assumed to absorb a supply-oriented production. The transport function in such an environment relies on economies of scale with delays at transfer points such as ports and rail yards.
In a Post-Fordist environment, supply chain management tends to reduce the need for warehousing and increase the integration between elements of the value chain in a complex network of relationships (e.g. outsourcing). This system is more demand-derived, with its elements adapting to constant fluctuations in the amount, origins, and destinations of cargo flows. Under such circumstances, the transport function is closely integrated into production and distribution and is the main element minimizing delays and warehousing. A share of the inventory is in circulation.