The aim of this paper is to describe and analyse a best practice event organized and managed by the Italian Public Administration concerning the achievement of UN’s Sustainable Development Goals (SDGs). Specifically, we are going to answer the following research questions: RQ1, Which approach is the most appropriate for the management of highly complex events and inter-institutional projects?; RQ2, Which is the connection between 2030 Agenda and great events? Large-scale events, which are characterized by a dynamic complexity involving different national public administrations and institutional levels, require a special attention in selecting an adequate event management systems. For this reason, after a detailed literature review on network management, this chapter aims to define the basics of a theoretical framework useful to understand collaboration among several actors, considering that participative approaches should help achieve outcomes in a more effective way. Furthermore, this paper explores the concept of sustainable development and focuses on the traditional elements of social, environmental and economic pillars within context of planned events. Given the objective of this work, the analysis of a best practice event will be useful to identify the main variables, in terms of sustainable strategic planning, execution and control, required to achieve the greatest level of efficiency in terms of cost optimisation and quality of service delivery, also exhorting the Italian public sector to look for a structural renewal, to better use its available resources, as well as to foster a global sustainable growth. From this point of view, a relevant experience is the case of the Extraordinary Jubilee of Mercy, coordinated by the Prefect of Rome, explored in the last section of the paper. Indeed, the latter, decided to adopt actions consistent with sustainability standards, thanks to the design of an inter-institutional network and the engagement of institutions at different levels. The Prefect of Rome achieved, in a very short term, three main results: coordination of the activities of the working groups (SDG 17, “Strengthen the means of implementation and revitalize the Global Partnership for Sustainable Development”); integration of internal and external surveillance and communication systems (SDG 9, “Build resilient infrastructure, promote inclusive and sustainable and foster innovation”); collaboration with higher education institutions to acquire and disseminate knowledge (SDG 4, “Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all”). To systemise and combine the outcomes of these processes, as well as to analyse their consistency with sustainable development, the System Thinking technique was used.