The following may join the CIT as full members:
- undertakings which provide international rail transport under the terms of COTIF or under other international sets of regulations;
- undertakings which make use of CIT documentation or services.
Associations of undertakings with a legal personality may join the CIT as associate members provided their own members:
- provide international rail transport, or
- provide services in connection with international rail transport, or
- make use of CIT documentation or services.