»The Restriction or Foreign Direct Investment in Security-Related Civilian Companies. A Constitutional and Union Law Analysis of Foreign Trade Law Provisions with Special Consideration of Media Companies«: Cross-sectoral investment screening is becoming increasingly significant both politically and legally. This study takes the national FDI screening regime as an illustration and addresses the question of whether it is compatible with constitutional and European Union law. It is shown that the legal framework needs to be reformed due to the indeterminacy and disproportionality of the regulations. Recommendations for the practical use of the mechanism are given and reform proposals are developed.