As part of the free movement of individuals, the principle of free movement of workers is enshrined in Article 45 (previously Article 39 EC) of the Treaty on the Functioning of the European Union and its significance and content have been further developed through secondary legislation and the jurisprudence of the European Union Court of Justice. The principle provides to any national of a Member State of the European Union the right of access to employment and the right to conduct such an activity on the territory of another Member State, subject to limitations justified on grounds of public policy, public security and public health. The outcome pursued by the theoretical and practical approach of this issue consists in analyzing the principle from a triple perspective, namely from the point of view of regulations evolution, of highlighting the role of jurisprudence of the European Union Court of Justice in the process of normative framing and completion and of the level of its application.