Alexander Classen addresses the tension between democratically legitimized representation of interests and unlawful influence to the detriment of the public. In the public eye, the closeness of lobby groups to politics is often perceived as inappropriate, while at the same time, the political influence of lobbyists is increasing on the European stage. Starting from a structural analysis of the EU's political system, the author examines the current realpolitik situation for deficiencies in legality and develops regulatory proposals for more effectively preventing illegitimate and corrupt influence. In doing so, the author identifies socially relevant functions of interest representation that are of paramount importance for a modern society and have become indispensable for political institutions.