If you miss your train, first of all, take a deep breath and don't panic. You'll need to check the fare conditions of your ticket to see whether it can be changed. Learn more about each carrier's terms:
- Trenitalia
 - Renfe
 - Deutsche Bahn
 - SNCF
 - Eurostar
 - SBB
 - ÖBB
 - SNCB
 - NS
 - Iryo
 - České dráhy (ČD)
 - Dänische Staatsbahnen (DSB)
 
For more information, please refer to the related article: How can I change my ticket?