Introduction of a new process tool into semiconductor manufacturing typically involves an enormous investment in engineering time. Optimization of the selection, utilization and performance of a new kind of tool can sometimes be considerably facilitated with modeling. However, the goal of interest is often a feature or material with properties measured at the micrometer scale or below, while controls for the process may be available only on the meter scale. Spanning this gap is a significant challenge. This introductory talk will discuss some specific cases and a few of the methods that have been used to address pieces of the problem.