Over the last few years, the European Rail Traffic Management System (ERTMS) has been paving the way for harmonizing the European railway network. The first issue of standards has contributed to the installation of the systems throughout the European network. The setup of the new paradigm in the signaling area required and still requires combined efforts by all participating stakeholders, including manufacturers, infrastructure managers, national authorities and railway undertakings to embrace the challenge of harmonizing the railway area in Europe. This case study focuses on the deployment of the ERTMS system in Poland, its beginning, development, evolution over time, current and future perspectives on the way towards a unified railway network. Before ERTMS Poland has developed its protection system called SHP which has the capabilities for automatic train braking. The system comprises an antenna located underneath the vehicle and trackside electromagnets (also known as solenoids). When a train drives over the electromagnet, the system, tuned at a frequency of 1000HZ, is activated, conveys the information to the devices installed on the train and can trigger an emergency brake if not promptly acknowledged by the driver. Additionally, the analog Radiostop system operating at 150 MHz, serves as voice communication between drivers and dispatchers, with the capability to bring all nearby trains to a standstill during emergencies. While these legacy systems served Poland well, they created interoperability challenges with neighboring countries’ networks – the issue ERTMS was designed to solve. To read more about this article and to have full access to premium content SUBSCRIBE to Basic Subscription Plan or Premium Subscription Plan.