European citizens moving freely through EU face the problem that their eID documents from the home country do not allow access to the electronic services of another Member State where they are present. Considerable efforts have been made in several projects to face the challenges of pan-European interoperability of electronic authentication and to assess the feasibility of differing approaches. This report analyses the security risks of electronic authentication in cross-border solutions, in the light of two projects, NETC@RDS and STORK.