Graphical user interfaces can provide interactive and intuitive visual communication to fault simulation and analysis application programs, enhancing the capabilities of engineers to conduct studies with ease and flexibility. Unfortunately, such benefits often come at the price of efficient CPU utilization and more complicated maintenance activities. Employing a distributed architecture can mitigate these costs by trading the one-time cost of more complex design activities for the long term benefits of ease of use and efficient resource utilization. TUFTsim, a multi-level concurrent simulation system, has been designed to address these concerns and demonstrates that an extensible, distributed architecture can be created without incurring excessive cost in processor and resource consumption. In addition, the investment in this architecture has also yielded benefits with respect to long-term maintenance and other software engineering considerations.