Due to complexity in design Procedure of process engineering, it has been noted that integration of design process should be realized based on the concept of concurrent engineering. One of the primary issues for concurrent engineering is to construct communication environment among engineers who have different tasks at different sites. This can be achieved by sharing design information through agent-based collaboration. Management of decision revision among agents can be supported by rule-based system in order to track dependency among decisions and to maintain optimality in distributed design environment. In this paper, plant layout process in which three kinds of engineers are involved was applied as a case study in order to show how agent-based collaborative design can be implemented in chemical plant design.