Though flexible manufacturing systems have promised wide range of benefits but the implementation of FMS has fraught with difficulty as a result of which the implementation rate of FMS is much lower than has been expected. To bridge the gap efforts at global level are carried out widely in today’s global and informative world. In the progress, modelling plays a vital role in the design, planning, implementation and operation of FMSs. Models are used widely to provide insight into how the FMS system and its components interact. With time new optimization problems arises in FMS, thus new modelling methods and techniques and updation of the existing needs to be developed time to time. Since the publication of the first articles on the planning problems of FMS’s (Stecke Kathryn E. and Solberg James J., 1981)(Stecke, 1983b), much research has been devoted to the solution of these types of problems. The aim of this paper is to review the approaches to model FMS and the solution approaches. A review paper provides basis and direction for future research directions.