The development of new software or the refinement of existing software for new operating environments each calls for judicious balancing. On the one hand, we strive for simplicity, predictability, and operational protection as it is well recognized that software with these attributes will attract an audience of satisfied users. But, on the other hand, these attributes do not conjure a sense of power, efficiency, or flexibility, and these other properties are also appreciated by users, albeit a somewhat different group of users. The goal is to achieve a blend which isolates critical functionality, flexible control, and user support while meeting the needs of the broadest collection of serious users. In this chapter, we discuss the issues impacting the migration of SAAM to the Windows environment, the NIH WinSAAM Project, and we outline the steps taken to ensure its feasibility. In addition, we describe a new paradigm for software development and use which ensures the durability of the software for modeling.