Abstract: A computer aided design tool provides a user with the capability of generating a design implementation for electronic circuitry. In this system the user generates a design schematic specifying a functional description of a design for electronic circuitry without the need for specifying packaging information. The system is provided with a packaging tool for generating a physical package for the circuitry of the design schematic. Use of the packaging tool may be deferred until the design schematic has been completed and verified. Further, a user of the system has the option of specifying certain packaging information when creating the design schematic or delaying such specification until just prior to packaging of the design.