and analysis. Further, the graphical user interfaces used in most modeling systems are at best barely adequate to the required task. Critical work on these interfaces is required to continue pushing back the frontiers. Similarly, once the design is modeled, how are the varied and diverse pieces stored, retrieved, and modified? How are physical interferences prevented or eliminated? Although considerable progress has been made, there are still more questions and frustrations than answers. One of the fundamental problems of the 1990s is and will continue to be modeling. The second problem is interpretation. With the ever increasing computational power available, our ability to generate data far exceeds our ability to interpret, understand, and utilize that data.