The case study deals with the border obstacles caused by lacking technical interoperability between national railway systems as well as infrastructure bottlenecks caused by insufficient coordination of investment between countries. It particularly looks at the example of the railway link between Austria and Slovenia, which is part of the railway corridors linking central and western Europe to South-East Europe. The following main problems have been identified: Lack of technical interoperability (electrification, train control systems) requiring multi-system locomotives or change of locomotives at the border ; Infrastructure bottlenecks hampering capacity and speed (single track sections, limited axle load), mainly due to problems with the coordination of investment and investment prioritisation between different Member-States (MS) The major consequences of the lack of interoperability and infrastructure bottlenecks are: waiting times at the border hamper commercial speed and therefore lead to lower attractiveness for customers and to higher operational costs for the railway undertaking; problems with reliability and punctuality due to frequent delays ; financial costs for expensive multi-system equipment On top of these operational aspects, such bottlenecks aggravate the existing operational weaknesses of rail transport and contribute to the declining attractiveness of cross-border rail connections. This is particularly detrimental to the development of concerned (border) regions where competitive rail connections are crucial for certain industries and for cross-border labour mobility. The EU railway sector has been thoroughly reformed in the past 25 years. In freight and long-distance passenger transport, railway infrastructure is now open in a non-discriminatory way to all licensed railway undertakings. The building blocks of the ongoing reform process for overcoming border-crossing obstacles are: 1) Technical Specifications for Interoperability (TSI), i.e. the EU-wide harmonisation of technical standards and homologation procedures 2) The corridor approach as an attempt to foster EU-wide investment coordination There are European and bilateral cooperation structures in place tackling the cross-border obstacles and some progress is being made. However, the necessary investment in infrastructure and rolling stock is bound to take a long time and border regions rarely have priority in either country concerned.