This document represents the Proceedings of the 2023 International Conference on the Network of the Future (NoF 2023), that was held on October 4-6, 2023, in Izmir Turkey. Since its creation in 2010, NoF has been a premier annual conference that covers advances in the area of Future Internet design, with emphasis on enabling technologies, architectures and services. In recent years, networks have been witnessing a significant transformation that is resulting in new ways to address the deployment of applications and services in a digital society, today emphasized by the early deployment of 5G networks and services. Major trends like softwarization leveraged by Software-Defined Networking (SDN), Network Function Virtualization (NFV) and Cloud & Edge Computing, as well as the introduction of new radio techniques are shaping the evolution in the Telecom and ICT industries. Additionally, initial research on 6G networks and technologies has already been initiated. Besides technological advances, networking further benefit from the growing introduction of Artificial Intelligence and Machine Learning techniques that are expected to alleviate complexity while providing smart and reliable network operations. In addition to the five technical and one demo/poster session, this year’s program also includes three keynote talks. Finally, the program with complemented with one Panel about “How do we get from the current networks to the 5G vision”, and one Tutorial on Federated Learning for Security in Network Management.