Technology files and design rules are essential building blocks of the integrated circuit design process. Their accuracy and robustness over process technology, its variability and the operating conditions of the IC — environmental, parasitic interactions and testing, including adverse conditions such as electro-static discharge — are critical in determining performance, yield and reliability. Development of these technology and design rule files involves an iterative process that crosses boundaries of technology and device development, product design and quality assurance. Modeling and simulation play a critical role in support of many aspects of this evolution process.