A principal goal of concurrent engineering has been to reduce the development cycle and time-to-market for new products. The success of such efforts brings about a parallel need for rapid design, evaluation, and reconfiguration of the facilities required to manufacture these products. Traditional facility layout methods rely on a sequence of actions progressing through a series of increasingly detailed analyses. More recent techniques automate and improve this process. However, there has been little progress toward an integrated facility design environment that would support the interactions of multidisciplinary designer teams. Such teams have been created with significant benefits for realizing the concurrent engineering process, and can be more effective if given a common design language. This article describes the generic Facility Description Language (FDL), which provides a common formal base for collaborative work and detailed analysis of process layout, flow geometry, visual aspects of control and safety. FDL augments the capabilities of simulator-emulator design workstations to integrate the physical and logical aspects of production facility design. Specifically, our research has defined the basic features and functions of FDL and resulted in a prototype implementation architecture. FDL can serve as a useful structure for the definition and description of a production facility at different levels of abstraction, allowing the same basic design model to be iteratively refined throughout the development process. It is demonstrated how an interactive graphical environment provides a powerful modelling tool that permits distributed users to achieve a higher level of design synergy.