Comprehensive methodologies for information system development need to provide a framework for the adequate representation of system requirements and also for their usage in generating system designs. The generation of a design is achieved by mapping elements of the requirements model into one or more corresponding design objects. This mapping process is guided by two considerations. Locally, the process is directed by dependency types among requirements and design objects which determine allowable mappings for a particular requirements object. Globally, the process is guided by non-functional requirements which are represented as goals describing desirable properties of the intended system. Satisficing methods for these goals are used to guide local mapping decisions. The chapter includes the description of a prototype implementation — called IRIS — of aspects of the proposed mapping framework and illustrates its features through a sample session.