In Wachauf, a case concerning the regulation of milk production, the ECJ ruled that Member States are bound, when implementing EU law, by all the general principles and fundamental rights that bind the EU in its action. This application of fundamental rights can be explained by viewing Member States as agents of the EU when they implement or enforce EU measures, and thus are bound by the rights protected as part of EU law. This is a kind of judicial ‘human rights mainstreaming’ technique, in accordance with which EU legislation is strengthened by the imposition on Member States of an obligation to protect all the rights guaranteed by the Charter, and the general principles of EU law, when implementing such measures. - Case 5/88 Wachauf v Germany [1989] ECR 2609, [17]–[19]