An increasing part of European’s rail passenger and freight traffic is transnational. Multi-system locomotives and high speed trains are able to run under different power supply systems without significant additional hardware in the power circuits. However, among the most costly barriers in international rail traffic are different signalling systems as well as the homologation processes for rolling stock. One of the reasons for the differences in these processes is different requirements for compatibility between rolling stock and train detection systems. Electromagnetic interference which can lead to a reduction of reliability or even safety of these detection systems must be avoided, and rolling stock has to be designed and qualified accordingly. Since Europe’s railway systems have been optimised on a national level over numerous decades, corresponding requirements and test procedures deviate significantly from each other. This article shows how the Railcom project, cofunded by the European Commission, helps the standardisation bodies to find solutions which will lower the barriers for interoperable rail traffic in this specific field.