Prior to the establishment of the agency, the railway networks of each individual member state within the European Union had been unique and typically employing high levels of bespoke, self-developed working practices, rolling stock, and infrastructure; the requirements pertaining to safety, operations, signalling, and most elements were defined by each member state, resulting in substantial differences in various systems and thereby hundreds of factors for incompatibilities that deterred or outright prevented cross-border operations.

[2] Limitations to loading gauges, differing signaling apparatus, incompatible power systems, and often arbitrary standards cumulatively acted against the competitiveness of European railway operations, particularly in comparison to the relatively lower barriers present in the competing road transport sector.

[2] In successive years, additional legislation towards bolstering international cooperation and the lowering of national barriers were also implemented, such as in the Interoperability Directive of 2001 that covered the trans-European conventional rail.

[7][8] The ERA has also promoted more efficient rail freight operations, via improved logistics practices, such as optimised route planning and load consolidation, some of which having been facilitated via digital railway technologies.

[10] In September of that year, the agency issued its first single safety certificate; at the time, multiple other applications were stated to be underway while the process was still being rolled out into early 2020.

[11][12] The One-Stop Shop approach has been promoted as reducing the time and cost involved in gaining required approvals by an anticipated rate of 20 percent, which is expect to yield savings of up to €500 million by 2025.