The law of the European Union is enforced not only by member state authorities but increasingly also by private entities. Rose von Richthofen describes the structure, obligations, and legal consequences of this private enforcement from the perspective of German administrative law as well as Union law. It becomes clear that private enforcement does not replace official enforcement but rather complements it. While private entities do not act in an official capacity, they represent a part of the functional European administration. The author chooses European product approval law as a reference area, which has provided for private enforcement through the involvement of accredited notified bodies for years.