Member States of the EU are not free to award subsidies to their national companies or to support them in a comparable way (by, inter alia, securing favourable supply conditions to the companies, granting loans at favourable rates or providing unlimited guarantees). In the wake of the recent financial crisis, for instance, bailout measures adopted across the EU had to be cleared by the European Commission in accordance with Articles 107 and 108 TFEU. The first part of the course explores the economic rationale underpinning the control of State aid in the European Union (the reasons why similar regimes are not implemented at the national level in federal countries facing similar dilemmas, such as the United States, will also be explored). The second part examines (i) the notion of State aid within the meaning of Article 107(1) TFEU and (ii) the conditions under which measures falling under the scope of that provision may be deemed compatible with the internal market. The third part provides an overview of the application of the law in some sectors (including the financial and the communications sectors) or for some purposes (e.g. research and development, regional aid). Finally, the fourth part is devoted to the procedural aspects of the discipline.