Rail transport across political boundaries has existed for a long time. But a good rail service across borders requires coordination and agreement in many fields. Numerous technical standards have to be harmonized, but beyond that a common understanding of rail's role on the transport market and agreed service concepts are necessary. However, the policy and planning objectives are often different on each side of a border. The book presents an analysis of how common ideas and projects for cross-border transport were developed in the political and planning discourse. Service concepts, tariffs and infrastructure are covered as key areas of rail transport. Cases from the late 19th century and the decades after World War II are compared. Difficulties of taking steps (back) towards a "European" rail network can be experienced even today. The aim to unite Europe on rails often stands in contrast to the technical complexity of the railways, increasing competition and diverging ideas.