"Nowadays there is a growing uncertainty about the near future evolution of classical PMR solutions due to spectrum scarcity, digital dividend issues and economic crisis. GERYON aims at facing this situation by seizing the existing window of opportunity due to the convergence of the IMS as a predominant enabler for future multimedia networks and the imminent deployment of commercial LTE networks,.GERYON proposes an innovative emergency inter-networking system capable of connecting existing first responder communication systems and enabling the integration of next generation mobile networks by defining technology independent standardized interfaces and autonomic configuration and adaptation techniques under the umbrella of IMS.Therefore, GERYON will unify common technical and operational logic of first responder communications networks in a technology independent manner. This unification will offload interconnection gateways from duplicated technology dependent details by providing a neutral interconnection interface. Proposed system will ensure seamless operation regardless the access technology and take advantage of coverage and responsiveness of existing PMRs and broadband data services of 4G networks.GERYON will demonstrate both classical (i.e. PTT, MTP and preemptive calls) and enhanced emergency services (i.e. multimedia streaming and data services) over an across-frontier testbed. Furthermore, its capability for including general purpose IMS terminals and GERYON enhanced ones will allow an easy access to first responder networks to different groups of unprotected users such as elderly people, people with special needs and battered women that will take advantage of enhanced services such as the “Red Button” over general purpose devices."