Prior to founding Hagen Advisory , David Hagen gained 20 years of experience with the Commission de Surveillance du Secteur Financier (the Luxembourg's Financial Sector Regulator) as responsible for:

- the supervision of the information systems of the supervised entities
- the supervision of the Support PFS

He was also responsible for the CSSF's IT for 6 years.

In parallel to these activities, he has been teaching at the University of Luxembourg within the Master in Information Systems Security Management for 17 years.

He is a member of the Electronic Signature Committee of the Ministry of Economy (Ministerial Arrest of 17 December 2013).

Co-author of the following academic publications:

CLOUD PROVIDERS VIABILITY: HOW TO ADDRESS IT FROM AN IT AND LEGAL PERSPECTIVE? (Cesare Bartolini, Donia El Kateb, Yves Le Traon, David Hagen (2015))

OPERATIONAL RISK MANAGEMENT IN FINANCIAL INSTITUTIONS: PROCESS ASSESSMENT IN CONCORDANCE WITH BASEL II (C. Bernard, D. Hagen, P.Maar, D. Reinard, B. Di Renzo, M. Hillairet, M. Picard, A. Rifaut, (2005))

Lifetime Career" award from ITOne, received in 2017 from the Luxembourg ICT community in recognition of its commitment to the national IT sector.

He is a regular speaker at conferences and round tables organised by the ABBL , ALFI , ALRiM , ALCO , ISACA Luxembourg Chapter , IIA , etc.