Many years ago, the European Union set itself the ambitious goal of making railways safe and interoperable. One of the key ways of achieving this goal is the implementation of the European Rail Traffic Management System (ERTMS). The implementation of ERTMS in the EU has been going on for many years. In the Netherlands, for example, the first line equipped with ERTMS equipment is the Betuweroute, which took place in the early 2000s. The legal requirements for implementation have changed in the meantime. Expert Jakub Tomczak explains how this process goes.