1. This Directive establishes rules on the procedures for procurement by contracting authorities with respect to public contracts as well as design contests, whose value is estimated to be not less than the thresholds laid down in Article 4.

2. Procurement within the meaning of this Directive is the acquisition by means of a public contract of works, supplies or services by one or more contracting authorities from economic operators chosen by those contracting authorities, whether or not the works, supplies or services are intended for a public purpose.

3. The application of this Directive is subject to Article 346 TFEU.

4. This Directive does not affect the freedom of Member States to define, in conformity with Union law, what they consider to be services of general economic interest, how those services should be organised and financed, in compliance with the State aid rules, and what specific obligations they should be subject to. Equally, this Directive does not affect the decision of public authorities whether, how and to what extent they wish to perform public functions themselves pursuant to Article 14 TFEU and Protocol No 26.

5. This Directive does not affect the way in which the Member States organise their social security systems.