Simulation is commonly used as a decision tool by managers in marketing, engineering, production, finance and many other disciplines. Managers simulate processes to gain a better understanding of their processes, diagnose problems, train new employees, and explore possibilities. Both the advent of powerful personal computers and the development of graphically driven simulation packages have contributed to this greater adoption. This note describes process simulation and illustrates the techniques with a tutorial model of a deli operation. (An Extend simulation file, product 7A96D009, is available for this case.)