The spread of digital technologies, aiming at improving the effectiveness of the technological and environmental project proposals, has transformed the modus operandi for architects and designers who approach environmental impact assessment, especially about public space designs. Research activities aim at collecting guidelines for the sustainable regeneration of public spaces, focusing on the effectiveness of the performance of individual actions proposed by gradually checking and fixing the convenient benchmark design required by norms and sometimes by technology and building best-practices widely consolidated, even on a scientific basis. Early design optimization process relies on the combined use of appropriate IT tools for environmental control and on the interoperability of these systems with the traditional modeling tools for outdoor and indoor spaces. According to data-design-oriented logic, the core of the research methodology is applied to three case studies concerning public “complex” open spaces within the Neapolitan urban context (Italy).