This work has been done in a highly competitive context, where electronic-system designers require electrostatic discharge (ESD) protection devices providing high performance levels. The purpose of protection device is to make circuits robust against ESD event, while being totally invisible to the system during normal operation. In this work, several aspects of ESD protection device are discussed, and new testing methods are proposed. An overview of design issues related to the several aspects of ESD protection is outlined. A new design approach is proposed which aims to address a large range of applications and is based on a "flexible" technology of protection. We achieve this challenge using machine learning tools and physical simulations to explore and yield profit from the existing compromises between designs and process parameters. The final goal is to allow maximum design flexibility while providing guidance to easily adapt ESD protection to the targeted application-requirements.