Local buffers at the work stations in moat flexible manufacturing systems have very limited storage capacity and, consequently, parts attempting to enter the work stations may be blocked. Parts routing that follows a dynamic scheme adapted to the state of the system is also desirable. A set of models has been developed to accommodate these features of real systems. The models have easily computable solutions, and with small local buffers are robust to various processing-time distributions. For systems with large local buffers, they can readily incorporate the exponentialization approach to yield accurate results.