The B3G (Beyond 3rd Generation) vision is tending towards a global infrastructure where several systems can coexist to support transparent end-to-end communications in a cost-effective manner. An important issue for next generation wireless system will be coexistence and optimization to provide a “network-of-wireless-networks” accommodating a variety of radio technologies and mobile service requirements in a seamless cost-effective manner. To address these issues, the main focus of LOOP will be to explore innovative solutions targeting: Network Discovery, Session Management and Roaming to allow the end-user to maintain session continuity whilst roaming between operators and wireless technologies. Ad-Hoc Networking for Relay-based Cell Coverage Extension will extend wireless and mobile coverage providing enhanced QoS delivery, and extended service delivery to remote, and fringe users. Dynamic Spectrum Allocation for Heterogeneous Networks to investigate the opportunistic use of licensed spectrum by secondary systems to optimize utilization of scarce spectral resources. Intra-System Optimization to maximize network utilization by exploring the application of a cross-layered protocol architecture.