Projects are a form of engineered-to-order (ETO) production which require that the definition of Value becomes part of the production process. Project production requires the inclusion of the product design, the design process, and the production process to be integrated in order to fully benefit from waste reduction and process improvement. In construction, project production is more challenging because of the temporal, transient, and fragmented nature of the project team and the supporting supply chain. This requires a form of ‘interoperability’ between the supply chain organisations, the particular teams involved, the commissioning clients and other stakeholders. It is proposed that this ‘interoperability’ is a form of common understanding and that this understanding needs to be defined, developed, and nurtured across the project execution as a flow in the same way that other flows are managed. Building on the seven flow model proposal reported by Koskela and Howell (1999), this paper proposes a common understanding as an eighth flow and suggests how it might be managed. The paper classifies the concept of common understanding as a soft flow and shows that although it is a fresh insight it actually has roots in lean production. The identity of common understanding as the eighth flow arises from a number of funded research projects in which the difficulties of lean construction implementation were investigated.
Collaboration, flow, common understanding.