Christian has been active in various European committees on digital transformation for over 20 years and has developed national digital strategies for more than 10 countries worldwide. In his roles as spokesperson for the Digital Austria platform and Executive Secretary for eGovernment at the Austrian Federal Chancellery, he led the country from 13th place to first place in the EU eGovernment rankings within three years. The basis for this was the intensive collaboration in the design of interfaces and common standards between the federal government, federal states and local authorities.

Christian Rupp has been on the board of the National E-Government Competence Centre (NEGZ) since 2019 and has been Chairman of the Innovation Mine for Artificial Intelligence in Public Administration and Embassy of the EU Master AI4Gov since 2021.

The German digital newspaper Tagesspiegel recently called him "Mr Digitalisation". As chief strategist for e-government, he currently leads the OZG consulting teams at Prosoz for the State Ministry for Digital Affairs in Bavaria and numerous municipalities throughout Germany, among others.

Christian joined the WSA right in the beginning in 2003 and served on the Board of Directors for more than 20 years.