2 Concept ( Tools • Specification ( Tools + Design Stages ( Tools • Implementation ( Tools Figure 1-1. A nominal, multi-stage development process From that beginning, we have progressed to the point where the EDA community at large, including both users and developers of the tools, are interested in more unified environments. Here, the notion is that the tools used at the various stages in the development process need to be able to complement each other, and to communicate with one another efficiently using effective file exchange capabilities. Furthermore, the idea of capturing all the tool support needed for an EDA development into a unified support environment is now becoming a reality. This reality is evidenced by some of the EDA suites we now see emerging, wherein several tool functions are integrated under a common graphical user interface (GUI), with supporting file exchange and libraries to enable all tool functions to operate effectively and synergistically. This concept, which we illustrate in Figure 1- 2, is the true future ofEDA.