Facing the problem of enhancing the railway security with a systematic top-down approach (i.e. to search for an all-inclusive solution valid for all the conceivable threat scenarios) is judged by PROTECTRAIL members too ambitious even if it could generate potential economies of scale and effort rationalisation. The proposed PROTECTRAIL approach is therefore to split the problem of making the railway more secure into smaller asset-specific security problems (missions) for which it is easier to reach satisfactory solutions applicable and usable in different threat scenarios. Each sub-mission could be therefore better oriented to particularly significant areas of interest, resulting from risk analysis or from rail operator priorities. In a clear view of scope and performance goals, for each sub mission it will be easier to define, research and develop solutions in terms of architectures, technology deployment, as well as the necessary procedures, organizations to manage the specific issue. The PROTECTRAIL challenge is therefore to make interoperable the single asset-specific solutions and to conceive and design a modular architectural framework where each asset-specific solution can be “plugged”, that is the basis to assure a streamlined process of federation, integration and interoperability of respective solutions. The PROTECTRAIL project will address the following security sub-missions: protection of signal and power distribution systems against any terrorism act, track clearance, clearance of trains before and after daily use, staff clearance, luggage clearance control, passenger clearance control, freight clearance control, tracking and monitoring of rolling stock carrying dangerous goods, protection of communication and information systems, stations, buildings and infrastructure protection.