The increasing importance of service sector has caused greater interest of both scientific community and practitioners in examining new service development (NSD) and understanding the necessary conditions of successful service innovation. Significant changes happened in the Postal sector during the last decades forces postal organizations to think in terms of service innovation, quality of service parameters and new service development. Despite of this, the empirical research that has been undertaken concerning the process of developing new services in the Postal sector is rather limited. This paper examines the effective development of new services and some essential factors that should be taken into account in this process by postal enterprises. The present research was based on the case study approach. In-depth semi-structured interviews with managers of Poste Italiane were conducted. Based on the collected data analysis, our hypothesis about 4 main groups of NSD drivers was confirmed.