The development of competitive technologies is nowadays based on the detailed understanding of the relevant physico-chemical processes involved in. The general approach used for this Research Line involves the application of the basic principles of physics and chemistry to investigate and elucidate these processes, both experimentally and through suitable mathematical models. This allows for scaling the developed new technologies to all required scales, from the molecular one to that relevant for industrial productions. A qualifying aspect of this Research Line concerns the application of molecular physical chemistry and quantum chemistry to the analysis of complex reacting systems occurring in the processes of interest, either in fluid phase or on surfaces. The final aim of this approach is to highlight the determining steps of the examined process. Summarizing, the key words identifying the researches performed in this Research Line are: Quantum Chemistry, thermodynamics of reacting multiphase systems, chemical kinetics of reacting systems, transport processes of reacting systems, process safety, energy production, environmental processing, computational fluid dynamics of reacting systems, advanced materials, multi-scale and multi-physics modeling. Industrial processes with chemical implications, polymers and inorganic materials for advanced technologies, combustion processes and processes related to pollutants reduction and abatement, safety in industrial processes, process optimization and energy management. This Research Line, whose keynote feature is the “approach and methodology”, is today mainly focused on the following three themes: Process Development, Advanced Inorganic film growth and Energy, Environment & Safety, all belonging to the Applied Physical Chemistry Laboratory.