In order to achieve the objectives of that directive, technical specifications for interoperability (TSIs) are drawn up by the European Association for Railway Interoperability (AEIF), which acts as the joint representative body defined in the directive, bringing together representatives of the infrastructure managers, railway companies and industry.
A number of tools and methodologies had to be developed in order to prepare the TSIs. Pending the adoption of TSIs, and in order to guide the technical choices made in the projects in progress in several Member States, the Commission adopted two instruments: Decision 2001/260/EC on the characteristics of the European Rail Traffic Management System (ERTMS) and Recommendation 2001/290/EC on the basic parameters of the trans-European high-speed rail system. A programme to develop the corresponding European standards was launched in 1998 and is regularly updated to reflect the work on TSIs.
The vast majority of Member States have notified national measures transposing the directive in national law as well as the independent bodies responsible for assessing the conformity and/or suitability for use of the interoperability constituents and for EC verification of subsystems.
The Commission has adopted in May 2002 the Technical Specifications for Interoperability for 6 subsystems (the texts of the TSIs have been published in the Official Journal L245 of 12 September 2002) and published in 2003 a Guide for the application of the High-Speed TSIs of Council Directive 96/48.






