Flexible Manufacturing Systems (FMSs) are the latest stage of automation comprising flexible machines and automated material handling systems functioning under the control of computers. The potentials of a Flexible Manufacturing System (FMS) can be fully realized by integrating the island of automation in to a distributed processing system. This paper presents a Knowledge Based Networking Selection (KBNS) in an FMS. The Knowledge Based (KB) methodology helps in decision making about the selection of networking architecture, access control methods, protocols and transmission media. The KB methodology is developed by using an Expert System (ES) shell called AM.