This paper presents a discrete event Monte-Carlo simulation based decision support system (DSS), which helps in managing business processes. Process managers use available information on work load, resource availability, task time, etc. and use their experience to predict the performance of the process and take corrective action, if required. We describe here a method and a system which takes available information about work load, and resource availability, to predict near future system performance using discrete event simulation, and compares the expected performance with desired service level and alerts the manager to take corrective action. The DSS assists operational managers in handling more complexity in decision making. This paper describes the framework for design of such a system which can be used in conjunction to a business process Management system.