System-level events, such as process switching and task migration, have a major effect on the pelformance of computer systems. ?Smart? is a new simulation environment that extends existing simulators, such as MINT with the capability to emulate the effect of such mechanisms. ?Smart? provides a user friendly inte@ace (GUI) that allows control of different system parameters and mechanisms e.g. the type of cache coherency protocols, cache organization, scheduling policies of processes and threads, etc. The Smart environment can be used either for monitoring, analyzing and measuring d@erent system events, or as a powerful visual based debugging tool. This paper describes the ?Smart? environment and demonstrates the importance of simulating system-level mechanisms and events in order to understand the overall performance of modern architectures. The Smart simulator presented here was developed to support the simulation of shared memory architectures, and we indicate that similar software environments can be developed to simulate other parallel and distributed architectures as well.