The European Commission has published a proposal for a Council Directive on the interoperability of the European high-speed network. The Directive concerns the design, construction, gradual placing in service and operation of the Community-wide high-speed train network. The network consists of links likely to be travelled by railway rolling stock that are suitable for high speeds. The overall geographical and physical data relating to the system is as follows: - Master plan; - Different types of line; - Rolling stock; - Coherence of infrastructure and rolling stock. The Directive applies to the provisions concerning, for each subsystem, the parameters, constituents, interfaces and procedures needed in order to ensure interoperability within the European high-speed network. The eight subsystems are as follows: - Infrastructure; - Energy; - Maintenance; - Signalling control/command; - Rolling stock; - Environment; - Operation; - Users. Each subsystem is covered by a technical specification for interoperability (TSI) which will determine the sensitive constituents and interfaces necessary in order to achieve interoperability. Sensitive constituents must bear the "CE" declaration of conformity, which will be subject to a checking procedure.